Compositions and methods for determining genetic polymorphisms in the TMEM216 gene

ABSTRACT

In alternative embodiments, the invention provides nucleic acid sequences that are genetic polymorphic variations of the human TMEM216 gene, and TMEM216 polypeptide encoded by these variant alleles. In alternative embodiments, the invention provides methods of determining or predicting a predisposition to, or the presence of, a ciliopathy (or any genetic disorder of a cellular cilia or cilia anchoring structure, basal body or ciliary function) in an individual, such as a Joubert Syndrome (JS), a Joubert Syndrome Related Disorder (JSRD) or a Meckel Syndrome (MKS). In alternative embodiments, the invention provides compositions and methods for the identification of genetic polymorphic variations in the human TMEM216 gene, and methods of using the identified genetic polymorphisms and the proteins they encode, e.g., to screen for compounds that can modulate the human TMEM216 gene product, and possibly treat JS, JSRD or MKS. In alternative embodiments, the invention provides cells, cell lines and/or non-human transgenic animals that can be used as screening or model systems for studying ciliopathies and testing various therapeutic approaches in treating ciliopathies, e.g., JS, JSRD or MKS.

RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.14/079,397, filed Nov. 13, 2013, now pending, which is a continuation ofSer. No. 13/098,345 filed Apr. 29, 2011, now U.S. Pat. No. 8,614,094.The aforementioned applications are expressly incorporated herein byreference in their entirety and for all purposes.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

This invention was made with Government support under NS048453 awardedby the National Institutes of Health. The Government has certain rightsin the invention.

FIELD OF THE INVENTION

This invention generally relates to human genetics and diagnostics, andmedicine. In alternative embodiments, the invention provides nucleicacid sequences that are genetic polymorphic variations of the humanTMEM216 gene, and TMEM216 polypeptide encoded by these variant alleles.In alternative embodiments, the invention provides methods ofdetermining or predicting a predisposition to, or the presence of, aciliopathy (or any genetic disorder of a cellular cilia or ciliaanchoring structure, basal body or ciliary function) in an individual,such as a Joubert Syndrome (JS), a Joubert Syndrome Related Disorder(JSRD) or a Meckel Syndrome (MKS). In alternative embodiments, theinvention provides compositions and methods for the identification ofgenetic polymorphic variations in the human TMEM216 gene, and methods ofusing the identified genetic polymorphisms and the proteins they encode,e.g., to screen for compounds that can modulate the human TMEM216 geneproduct, and possibly treat JS, JSRD or MKS. In alternative embodiments,the invention provides cells, cell lines and/or non-human transgenicanimals that can be used as screening or model systems for studyingciliopathies and testing various therapeutic approaches in treatingciliopathies, e.g., JS, JSRD or MKS.

INTRODUCTION

Joubert syndrome is characterized by a distinctive cerebellar andbrainstem malformation, hypotonia, developmental delays, and eitherepisodic hyperpnea or apnea or atypical eye movements or both. Mostchildren with Joubert syndrome develop truncal ataxia and delayedacquisition of gross motor milestones is common. Cognitive abilities arevariable, ranging from severe mental retardation to normal. Thedelineation of the phenotypic spectrum of Joubert syndrome remainsunresolved, and both intra- and interfamilial variation are seen. Otherfeatures sometimes identified in Joubert syndrome include retinaldystrophy, renal disease, ocular colobomas, occipital encephalocele,hepatic fibrosis, polydactyly, oral hamartomas, and endocrineabnormalities.

The current diagnosis of Joubert syndrome is based on the presence ofcharacteristic clinical features and the “molar tooth sign” on cranialmagnetic resonance imaging (MRI), resulting from hypoplasia of thecerebellar vermis and accompanying brainstem abnormalities on axialimaging through the junction of the midbrain and pons (isthmus region).The resulting images resemble the section of a tooth. Currently, fourcausative genes have been identified in which mutations appear toaccount for no more than 10% of cases of Joubert syndrome each areNPHP1, CEP290, AHI1, and TMEM67 (MKS3); other causative genes to thisdate were unknown. Molecular genetic testing is clinically available forall four genes.

Joubert syndrome is inherited in an autosomal recessive manner. Atconception, each sibling of an affected individual has a 25% chance ofbeing affected, a 50% chance of being an asymptomatic carrier, and a 25%chance of being unaffected and not a carrier. Once an at-risk sib isknown to be unaffected, the chance of his/her being a carrier is 2/3.Carrier testing for at-risk family members is available if the mutationshave been identified in the proband. Prenatal diagnosis for mutations inAHI1, CEP290, TMEM67, and NPHP1 mutations is available if the mutationshave been identified in the proband or carrier parents. Prenataldiagnosis using ultrasound examination with or without fetal MRI hasbeen successful.

Although diagnostics are available for Joubert syndrome, the currentlack of specificity is unsatisfactory. Therefore, what is needed are newgenes that are identified on the basis of their genetic linkage toJoubert Syndrome and Related Disorders (JSRD) and other ciliopathies,including Meckel Syndrome (MKS), particularly in the Ashkenazi Jewishpopulation. It is desirable to identify naturally existing deleteriousmutations in the genes which may serve as valuable diagnostic markers.

TMEM216 localizes prominently around the primary cilium, and patientfibroblasts show defective ciliogenesis and centrosomal docking, withconcomitant hyperactivation of RhoA and Dishevelled. TMEM216 complexedwith Meckelin, encoded by a gene also mutated in JSRD and MKS, andabrogation of tmem216 expression in zebrafish led to gastrulationdefects that overlap with other ciliary morphants. The data implicate anew family of proteins in the ciliopathies, and further support allelismbetween ciliopathy disorders.

The “ciliopathies” are a newly emerging group of diseases due to defectsin the function or structure of cellular primary cilia, which are smallcellular appendages previously of unknown function. Recent discoverieshave identified that a host of genes of previously unknown function playessential roles at primary cilia, which are mutated in diseasesincluding but not limited to obesity, polycystic kidney disease, mentalretardation, retinal blindness, ataxia, liver fibrosis, and some formsof cancer.

SUMMARY

In alternative embodiments, the invention provides compositions andmethods for the identification of genetic polymorphic variations in thehuman TMEM216 gene, and methods of using the identified geneticpolymorphisms.

In alternative embodiments, the invention provides methods ofdetermining or predicting a predisposition to, or the presence of, aciliopathy (or any genetic disorder of a cellular cilia or ciliaanchoring structure, basal body or ciliary function) in an individual,comprising:

(a) (i) determining the presence or absence of at least oneTransmembrane Protein 216 (TMEM216) genetic variant in the individual,wherein the at least one TMEM216 genetic variant comprises an amino acidvariation (from wild type) selected from the group consisting of R73L,R73H, R73C, L133X, L114R, G77A and R85X,

(ii) determining or predicting a predisposition to, or the presence of,a Joubert Syndrome (JS), a Joubert Syndrome Related Disorder (JSRD), aciliopathy (or a genetic disorder of a cellular cilia or cilia anchoringstructure, basal body or ciliary function), and/or a Meckel Syndrome(MKS)

wherein the presence of at least one of the TMEM216 amino acid variantsindicates a predisposition to, or the presence of, a Joubert Syndrome(JS), a Joubert Syndrome Related Disorder (JSRD), a ciliopathy (or agenetic disorder of a cellular cilia or cilia anchoring structure, basalbody or ciliary function), and/or a Meckel Syndrome (MKS).

(b) the method of (a), comprising obtaining or isolating aTMEM216-comprising nucleic acid from the individual, wherein optionallythe TMEM216 nucleic acid is an RNA, a DNA, a cDNA or a genomic DNA; or

(c) the method of (a) or (b), further comprising embodying thedetermining or predicting a predisposition to, or the presence of, stepin a communicable form for communication to the individual and/orphysician; wherein optionally the communicable form comprises a computerprogram product for communication to the individual and/or physician;and optionally the computer program product enables internet ortelecommunications to the individual and/or physician.

In alternative embodiments of the methods, the amino acid variationcomprises or consists of a R73L amino acid variation; or the amino acidvariation comprises or consists of a R73H amino acid variation; or theamino acid variation comprises or consists of a R73C amino acidvariation; or the amino acid variation comprises or consists of: a R73Land a R73C amino acid variation; a R73L and a R73H amino acid variation;a R73H and a R73C amino acid variation, or a R73L, R73H and a R73C aminoacid variation; or any combination thereof.

In alternative embodiments of the methods, the ciliopathy is a JoubertSyndrome Related Disorder (JSRD) amino acid variation, a JoubertSyndrome or a Meckel Syndrome (MKS).

In alternative embodiments of the methods, the step of determining thepresence or absence of at least one tmem216 genetic variant in theindividual, or determining one or more or all of the tmem216 geneticvariants in the individual, comprises:

(a) a sequencing, or a determining the sequence of, a TMEM216 nucleicacid obtained from the individual, optionally comprising a Maxim-Gilbertsequencing procedure (method, assay);

(b) a nucleic acid hybridization to a TMEM216 nucleic acid obtained fromthe individual;

(c) a polymerase chain reaction (PCR) assay, or a chain-terminatormethod (procedure, assay) (or Sanger method), or an emulsion PCR assay;

(d) amplifying a portion of a TMEM216 nucleic acid obtained from saidpatient and determining the presence of a genetic variation;

(e) a SOLiD (Sequencing by Oligonucleotide Ligation and Detection)method (Life Technologies, Carlsbad, Calif.);

(f) a high-throughput sequencing technology, or a DNA nanoballsequencing method;

(g) a Massive Parallel Signature Sequencing (MPSS);

(g) a dye-terminator sequencing procedure, a reversible dye-terminatorsequencing procedure, or an Illumina (Solexa) sequencing process:

(h) an ion semiconductor sequencing (e.g., by Ion Torrent Systems Inc.);or

(i) a parallelized version of pyrosequencing (454 Life Sciences.Branford.

Connecticut).

In alternative embodiments, the invention provides isolated, syntheticor recombinant nucleic acids comprising or consisting of:

(a) a sequence selected from the group consisting of SEQ ID NO:3, SEQ IDNO:5, SEQ ID NO:8, SEQ ID NO: 11, and sequences completely complementarythereof: or

(b) a nucleic acid encoding a polypeptide having an amino acid sequenceof SEQ ID NO: 1, SEQ ID NO:6, SEQ ID NO:9 or SEQ ID NO: 12, andsequences completely complementary thereof;

(c) a nucleic acid encoding a human Transmembrane Protein 216 (TMEM216)amino acid variant having an amino acid sequence of SEQ ID NO: 1, and anamino acid variation selected from the group consisting of R73L, R73H,R73C, L133X, L114R, G77A and R85X; or any combination of R73L, R73H,R73C, L133X, L114R, G77A and R85X; or all of R73L, R73H, R73C, L133X,L114R. G77A and R85X;

(d) a nucleic acid encoding the polypeptide of any of (a) to (c),wherein the amino acid variation comprising or consisting of R73L;

(e) a nucleic acid encoding the polypeptide of any of (a) to (c),wherein the amino acid variation comprising or consisting of R73H;

(f) a nucleic acid encoding the polypeptide of any of (a) to (c),wherein the amino acid variation comprising or consisting of R73C;

(g) a nucleic acid encoding the polypeptide of any of (a) to (c),wherein the amino acid variation comprising or consisting of L133X;

(h) a nucleic acid encoding the polypeptide of any of (a) to (c),wherein the amino acid variation comprising or consisting of L114R;

(i) a nucleic acid encoding the polypeptide of any of (a) to (c),wherein the amino acid variation comprising or consisting of G77A; or

(j) a nucleic acid encoding the polypeptide of any of (a) to (c),wherein the amino acid variation comprising or consisting of R85X.

In alternative embodiments, the invention provides isolated, syntheticor recombinant polypeptides (or proteins or peptides) comprising orconsisting of:

(a) an amino acid sequence of SEQ ID NO:1, SEQ ID NO:6, SEQ ID NO:9 orSEQ ID NO:12;

(b) a human TMEM216 amino acid variant having an amino acid sequence ofSEQ ID NO: 1, and an amino acid variation selected from the groupconsisting of R73L, R73H, R73C, L133X, L14R, G77A and R85X; or anycombination of R73L, R73H. R73C, L133X, L114R, G77A and R85X; or all ofR73L, R73H, R73C, L133X, L114R, G77A and R85X:

(c) the polypeptide of (a) or (b), wherein the amino acid variationcomprises or consists of a R73L;

(d) the polypeptide of (a) or (b), wherein the amino acid variationcomprises or consists of a R73H;

(e) the polypeptide of (a) or (b), wherein the amino acid variationcomprises or consists of a R73C:

(f) the polypeptide of (a) or (b), wherein the amino acid variationcomprises or consists of a L133X:

(g) the polypeptide of (a) or (b), wherein the amino acid variationcomprises or consists of a L114R;

(h) the polypeptide of (a) or (b), wherein the amino acid variationcomprises or consists of a G77A; or

(i) the polypeptide of (a) or (b), wherein the amino acid variationcomprises or consists of a R85X.

In alternative embodiments, the invention provides isolated, syntheticor recombinant, or hybridoma-generated, antibodies (or antigen bindingfragments thereof) selectively immunoreactive (that selectively bindsto) an isolated, synthetic or recombinant polypeptide of the invention(or encoded by a nucleic acid of the invention), wherein optionally theantibody is a monoclonal or a polyclonal antibody, or an IgG. IgM, IgAantibody, or a partially or fully humanized antibody.

In alternative embodiments, the invention provides arrays, ormicroarrays, or chips, or microchips, or any solid or semisolid surface,comprising at least one antibody of the invention; or one isolated,synthetic or recombinant nucleic acid of the invention; or at least oneisolated, synthetic or recombinant polypeptide of the invention; or anycombination thereof.

In alternative embodiments, the invention provides vectors, plasmids orexpression systems (or equivalents) comprising at least one isolated,synthetic or recombinant nucleic acid of the invention (which includesany nucleic acid that encodes a polypeptide of the invention).

In alternative embodiments, the invention provides cells, e.g.,transformed or transfected cells, e.g., mammalian cells, e.g., humancultured or isolated cells, comprising at least one isolated, syntheticor recombinant nucleic acid of the invention, or at least one vector,plasmid or expression system (or equivalents) of the invention.

In alternative embodiments, the invention provides nonhuman transgenicanimals comprising a heterologous nucleic acid comprising at least oneisolated, synthetic or recombinant nucleic acid of the invention, or atleast one vector, plasmid or expression system (or equivalents) of theinvention.

In alternative embodiments, the invention provides methods for screeningfor a compound that modulates (modifies) the activity or expression of aTMEM216 gene product, or a TMEM216 protein, comprising:

(a) (i) providing at least one isolated, synthetic or recombinantpolypeptide of claim 9;

(ii) providing a test compound; and

(iii) contacting the test compound with the at least one isolated,synthetic or recombinant polypeptide, and determining whether the testcompound modulates (modifies) the expression or activity of the at leastone isolated, synthetic or recombinant polypeptide, wherein determiningthat the test compound modulates or modifies the expression or activityof the at least one isolated, synthetic or recombinant polypeptideidentifies the test compound as a modulator or modifier of) the activityor expression of a TMEM216 gene product, or a TMEM216 protein:

(b) the method of (a), wherein the test compound comprises a protein, asmall peptide or a derivative or mimetic thereof; a non-peptide smallmolecule; a carbohydrate; a nucleic acid; a lipid or a fat; or an analogthereof;

(c) the method of (a), wherein determining that the test compoundmodulates or modifies the expression or activity of the at least oneisolated, synthetic or recombinant polypeptide is based on a bindingaffinity of a test compound capable of interacting with or binding to aTMEM216 protein variant; or

(d) the method of (a), wherein the at least one isolated, synthetic orrecombinant polypeptide of the invention is immobilized, optionallyimmobilized on an array or microarray.

In alternative embodiments, the invention provides computer programproducts for communication to an individual and/or physician conveyingthe results of the method of claim 1; and optionally the computerprogram product enables internet or telecommunications to the individualand/or physician. In alternative embodiments, the invention providescomputers having a computer program product of the invention.

The details of one or more embodiments of the invention are set forth inthe accompanying drawings and the description below. Other features,objects, and advantages of the invention will be apparent from thedescription and drawings, and from the claims.

All publications, patents, patent applications cited herein are herebyexpressly incorporated by reference for all purposes.

BRIEF DESCRIPTION OF DRAWINGS

The patent or application file contains at least one drawing executed incolor. Copies of this patent or patent application publication withcolor drawing(s) will be provided by the Office upon request and paymentof the necessary fee.

Those of skill in the art will understand that the drawings, describedbelow, are for illustrative purposes only. The drawings are not intendedto limit the scope of the present teachings in any way.

FIG. 1A-E illustrate Mutations in the TMEM216 gene in patients linked tothe JBTS2 and MKS2 loci: FIG. 1(a) schematically illustrates thechromosomal location of the JBTS2 and MKS2 loci on Chr. 11cent. FIG.1(b) schematically illustrates TMEM216 genomic organization, depictingstart and stop codon, and location of identified base changes. FIG. 1(c)schematically illustrates the longest splice isoform, which encodes fora 148 amino acid (aa) tetraspan membrane protein (SEQ ID NO: 1). Patientmutations predominate towards the middle of the gene, with R73 changesincluding R73L, R73H, R73C, and with one prevalent R73 change occurringrepeatedly. Missense, nonsense and splice mutations were identified.

FIG. 1(d) illustrates evolutionary conservation of mutated amino acids.FIG. 1(e) illustrates a Western blot of whole lysate of cellstransfected with a cDNA encoding wild type (WT) versus (vs.) patientmissense mutations, compared with control (V71L). Each mutation resultedin the production of 40-50% of WT protein levels, compared withα-tubulin loading control. Patient mutations lead to unstable proteinproducts.

FIG. 2A-J illustrate expression analysis, cDNA representation, andciliary localization of TMEM216: FIG. 2(a) illustrates a Northern blot(20 weeks (w) gestation human fetal tissues) using full-length TMEM216with 1.4 kb band in all tissues tested. FIG. 2(b) schematicallyillustrates a representation of recovered TMEM216 splice isoform clones(n=48) from 20 w gestation human fetal brain cDNA. No single majorityisoform was identified, but the longest and most prevalent encoded apredicted protein of 148 aa, which corresponds to EST BI910875. FIG.2(c-h) illustrate expression of TMEM216 based upon in situ hybridizationin human embryonic tissue (FIG. 2c to FIG. 2h ) antisense, (c‘-g’) sensecontrol probes. FIG. 2(c) illustrates Carnegie stage (CS)12, i.e. 4gestational weeks (gw), TMEM216 is ubiquitously expressed withinembryonic tissues in transverse section: neural tube (nt), heartprimordium (h). Fig. (d-f) illustrate CS15 (5gw) expression is moreintense particularly in nt, dorsal root ganglia (drg), mesonephros (mn),gonadal ridge (go) and limb bud. FIG. 2(g) illustrates 8gw strong signalin kidney, gonad and adrenal. FIG. 2(h) illustrates 8gw with specificexpression in CNS in particular in cerebellar bud (cb), cranial nerveganglia (trigeminal V, facioacoustic VII+VIII) and cartilage anlages(csc), with lower expression in telencephalon. (tel). FIG. 2i and FIG.2j ) (FIG. 2i is the top row three panels, and FIG. 2j is the bottom rowthree panels) illustrate indicated cell types (IMCD3 and hRPE,respectively) showing overlapping localization of some endogenousTMEM216 (green) and Ac-tubulin or GT335 (glutamylated tubulin) (red) ator near the primary cilium. Scale bar 5 um.

FIG. 3 A-E illustrate TMEM216 mutation or knockdown results in impairedciliogenesis and centrosome docking: FIG. 3(a) illustratesimmunostaining of two different TMEM216-mutated patient fibroblastslines to show defective ciliogenesis and impaired centrosome docking(marked by γ-tubulin). Scale ba: left 20 um; right 1 um. FIG. 3(b)illustrates a Western blot showing the specificity of TMEM216 antiserumtowards endogenous protein. Control fibroblasts show 27 and 19 kD bands,which are reduced in TMEM216 p.R85X fibroblasts (some residual isapparent likely due to read-through from geneticin treatment), as wellas in siRNA1-treated IMCD3 cells (especially the 19 dK band).Fibro.=fibroblasts; Non-transf.=nontransfected; scr.=scrambled. FIG.3(c) illustrates cell staining of transfected IMCD3 cells showing effectof Tmem216 siRNA treatment, with reduced ciliogenesis and centrosomedocking (note lack of cilia and lack of apically located centrosomesfollowing knockdown) Top is x-y, and bottom is x-z projection, scale bar10 um. FIG. 3(d) graphically illustrates that the percent of ciliatedcells (defined as cilia>1 um length) is reduced following Tmem216 siRNAtreatment. Percent cells with apical basal bodies (defined as mostsuperior 1.0 um sections compared to nuclear position) is similarlyreduced. * p<0.01, ** p<0.001, chi-squared test. FIG. 3(e) illustratescell staining showing a method of quantification at 72 hrs. Scale bars:white, most apical 1.0 um; grey, basal 1.5 um.

FIG. 4A-F illustrate TMEM216 is part of a complex with Meckelin and itsloss results in Rho hyperactivation, with resultant alteration in actincytoskeleton: FIG. 4(a) illustrates an immunoblotting of whole cellextract (input WCE) from TMEM216-GFP transfected HEK293 cells confirmedexpression of tagged TMEM216 at approximately 37 kD (arrow).Immunoprecipitation (IP) of WCE with anti-Meckelin antisera againsteither the Nor C-termini confirmed a complex with GFP-tagged TMEM216(arrowhead), which was absent in control IPs with an irrelevant antibody(irr. Ab; anti-Efe4) or the preimmune antiserum. Arrow is IgG heavychain. FIG. 4(b) illustrates an immunoblotting of a reciprocal IP of a60 kD C-terminal containing isoform of endogenous Meckelin from WCE ofTMEM216-GFP transfected HEK293 cells with anti-meckelin C-terminus(arrowhead), but not by either a no Mab control or an irrelevantantibody (anti-c myc). Arrow is IgG heavy chain. FIG. 4(c) illustratesan immunoblotting of MKS2 fibroblast WCE shows a 6.8-fold increase inlevels of activated RhoA-GTP compared to normal control. FIG. 4(d)illustrates an immunoblotting of an siRNA knockdown of Tmem216 in IMCD3cells, which caused a 7.6-fold increase in RhoA activation, comparedwith control. Mks3 positive control siRNA also induced a comparableincrease (7.7-fold) as reported previously (23). Total RhoA and 3-actinare shown as loading controls. Positive controls for the assays (+;loading with non-hydrolyzable GTPγS) and a negative control (−; loadingwith GDP) are also shown. FIG. 4(e) illustrates cell staining showingthat RhoA (red) localizes to the basal bodies (γ-tubulin, green) inIMCD3 cells following 24 hr treatment with scrambled siRNA, butmislocalizes to regions adjacent to the basal bodies (arrows and inset)and at basolateral surfaces (arrowheads) following Tmem216 knockdown.Mislocalization of γ-tubulin is also apparent (bottom inset). FIG. 4(f)illustrates cell staining showing subcellular phenotypes of fibroblastscultured from undiseased control and two individuals (162 and 186) withMKS, homozygous for the TMEM216 nonsense mutation p.R85X and compoundheterozygous for the MKS3 mutations [p.M261T]+[p.R217X], as indicated.Note prominent actin stress fibers in both mutated cells (arrowheads) asdetected by phalloidin staining, with mislocalization of Meckelin andfilamin-A to these fibers. Bar: 10 um.

FIG. 5A-G illustrate TMEM216 disruption results in Dvl1 phosphorylation,and planar cell polarity-like phenotypes in zebrafish: FIG. 5(a)illustrates an IP showing that siRNA knockdown of Tmem216 in IMCD3 cellsand TMEM216 p.R85X patient fibroblasts causes an increase in the upper(phosphorylated) isoform (P-Dvl1) (left panel). Treatment with the cellpermeable Rho inhibitor exoenzyme-C3-transferase (2 ug/ml) in IMCD3cells caused constitutive Dvl1 phosphorylation. The stimulatory effectof TMEM216 loss on Dvl1 phosphorylation was reversed by Rho inhibition(right panel) FIG. 5(b) illustrates a coimmunoprecipitation of both Dvl1and RhoA with TMEM216 in TMEM216-GFP transfected cells. Arrowheadindicates Ig fragment. FIG. 5(c) graphically illustrates data showing adose-dependent rescue of centrosome/basal body docking phenotype inTmem216 siRNA-treated cells following Rho inhibition. * p<0.01; **p<0.001, for chi-squared test. FIG. 5(d) schematically illustratesinjection of translation-blocking morpholino (MO) to tmem216 vs.scrambled MO in zebrafish results in a ciliary defect phenotype (curvedtail, small brain) in the majority of injected embryos (>50 eachcondition). Injection of human TMEM216 RNA shows no phenotype in wtembryos, but can at least partially rescue the MO phenotype in adose-dependent fashion (quantified below). FIG. 5(e) schematicallyillustrates Lateral (top) and dorsal (bottom) views of zebrafish embryosinjected with tmem216 or mks3 MO at 8-somite stage demonstrating commonciliopathy features including shortened body axis, wide undulatingnotochord, thin and elongated somites and small anterior structures.FIG. 5(f) schematically and graphically (bottom two panels) illustratesrepresentative 11-somite stage embryos hybridized with krox20. pax2, andmyoD riboprobes. Arrows indicate measurement points at the fifthrhombomere (horizontal arrow) and length of the notochord as indicatedby adaxial cell labeling (vertical arrow). FIG. 5(g) illustrates aGraphic quantification showing the severity of gastrulation defect intmem216 and mks3 morphants, measured along two different axes(convergence to the midline as indicated by the width at the fifthrhombomere, and extension along the AP axis as indicated by notochordlength: n=12-15 embryos/injection). Suppression of tmem216 or mks3resulted in significantly different width and length measurementscompared to controls (* p<0.005); the AP extension defect is morepronounced in the mks3 compared with tmem216 morphant (* p<0.005).

FIG. 6A-C illustrate MKS2 fine-mapping: FIG. 6(a) graphicallyillustrates results of the multipoint linkage analysis in 9consanguineous families with Affymetrix 10K SNP chips using MERLINsoftware assuming a fully penetrant recessive model with a diseaseallele of frequency 0.0001 and allowing for heterogeneity betweenfamilies. The highest heterogeneity lodscore (Hlod 9.179) was found atrs522073 on chromosome 11, at position 60.635. FIG. 6(b) illustrates intable form results of the Affymetrix 10K SNP: seven affected cases from6 families showed homozygosity at the refined MKS2 locus. F002delineated the interval between rs1113480 and rs953894 (48.014-62.518Mb). FIG. 6(c) illustrates in graphic and in table form thatHomozygosity was further confirmed by microsatellite markers analysisand suggested a founder effect by haplotype identity in 2 out of the 3Tunisian families (F2 and F5) and the 2 Palestinian families (F56 andF58) respectively. MKS15, MKS16 and MKS74 share the same haplotype andwere found to carry the same L114R TMEM216 mutation. No mutation wasfound in MKS860. MKS492 and MKS512 are also haploidentical and carry thesame G77A/T78KfsX30. Four heterozygous markers (white boxes) within thehomozygous region are probable allelic mutations.

FIG. 7A-B illustrate Chromatograms and RT-PCR analysis of the c.230G>Cmutation: FIG. 7A illustrates chromatograms of TMEM216 mutations foundin probands (upper panels). Lower panel shows normal controls. FIG. 7Billustrates analysis of the c.230G>C mutation at the cDNA level. Themutation is located at the first base of exon 5 and was suspected toalter splicing. RT-PCR was performed with primers located in TMEM216exon 4 (forward: GATGTGGTGATGCTCCTCCT) (SEQ ID NO:13) and 5 (reverse:CCAAGGTGAGCACCTCAAGT (SEQ ID NO: 14)) on RNA extracted from lymphocytescell lines in parents of fetus MKS492 and a control (C). Expected wildtype size is seen in control (244 bp) while in both heterozygousparents, 2 bands are observed: one corresponding to the wild typeallele, and another, corresponding to a larger transcript. Sequence ofthe father showed an abnormal transcript containing the last 46 bases ofintron 4 (boxed in blue, or the shaded box in the lower of the twoschematics of the spliced gene), by the use of an alternative splicesite (r.230G>C; 229_230ins230-46_230-1). The mutation is indicated inred on the sequence (i.e., is the 5′ most “C” residue in the box of the“Mut” sequence. The effect of the c.230G>C on the transcript is shown onthe lower panel, on the major and biggest isoform of TMEM216. The mutanttranscript predicts a truncated protein with a stop codon 30 amino acidsdownstream. The predicted effect on protein is p.T79Kfs30.

TMEM216 WT sequence is SEQ ID NO:15: GTACAAA GGGAAACCTC TGCCAGCGAAAGATGCCACT CAGTATTAGC GTGGCCTTGA CCTTC

TMEM216 Mut sequence is SEQ ID NO:16: GAAAA GCAGA CCATT TGGAG ATGACTCCAT GGGCT GTGTC TGACA GCTAC AAAGG GAAAC CT

The sequences illustrated in FIG. 7A are:

SEQ ID NO:35: is AGTAATTCTCCTGTTIT

SEQ ID NO:36: is GTAATTCACCTGTITT

SEQ ID NO:37: is AGTAATTCGCCTGTT

SEQ ID NO:38: is GAGCTTGACTTGAG

SEQ ID NO:39: is GTAATTCGCCTGTTT

SEQ ID NO:40: is AGTAATTCGCCTGTT

SEQ ID NO:41: is GAGCTITITACTTGAG

SEQ ID NO:42: is TACGTACGCCGCCTG

SEQ ID NO:43: is ACAGCTACAAAGGG

SEQ ID NO:44: is CTCTGCCAGTGAAAGATG

SEQ ID NO:45: is TACGTACTCCGCCTG

SEQ ID NO:46: is ACAGGTACAAAGGG

SEQ ID NO:35: is CTCTGCCAGCGAAAGATG.

FIG. 8 in table form illustrates Haplotypes of 10 of 12 JSRD familiesharboring the identical R73L mutation: Alleles (and markers) showingrecombination (gray) and homozygous (black) intervals, highlighting theshared homozygous region flanked by rs4245224 (centromeric) and D11S4076(telomeric).

FIG. 9A-K illustrate Clinical data of MKS and JS patients with TMEM216mutations: FIG. 9(a,b,e,h) illustrates case MKS-15 (21 w), FIG.9(c,d,f,i) illustrates case MKS-16 (14 w); FIG. 9 (g,j) illustratesMKS-512 (1 day). The picture illustrated as FIG. 9(a) shows theoccipital encephalocele, postaxial polydactyly, and distended abdomendue to polycystic kidneys; FIG. 9(b) illustrates X rays shows femoraland tibial bowing. FIG. 9(c) illustrates MKS-16 presents an anencephalicphenotype, FIG. 9(d) illustrates craniorachischisis and postaxialpolydactyly. FIG. 9(e-j) illustrate histological sections of kidnevs andliver show the cystic kidney dysplasia characteristic of MKS with largecysts both in cortex and medulla, growing in size from periphery tocenter. Histological sections of liver show the typical ductal plateanomaly in three cases with bile duct proliferation. FIG. 9(k)illustrates MRIs of control and JBTS2 patients. Top shows axial imagesat the level of the midbrain-hindbrain junction and the apparent “molartooth sign” (red arrows). Bottom shows midline sagittal sections and thehorizontally-oriented an thickened superior cerebellar peduncle (redarrow). Note that MTI-1008 has a large retrocerebellar cyst, withreduced cerebellar parenchymal volume. For MTI-467 (fetal MRI from anaffected and terminated pregnancy), and COR284, no sagittal images wereavailable.

FIG. 10A-B illustrate FIG. 10A graphically illustrates Band densitometryof Western analysis of FIG. 1e , showing reduced levels of TMEM216carrying any of the patient mutations, whereas a negative control aminoacid transversion (V71L) shows levels comparable to WT control. Cellswere co-transfected with a vector encoding β-gal; FIG. 10B graphicallyillustrates similar levels of 3-gal activity across samples, as acontrol for transfection efficiency.

FIG. 11 A-C illustrate Characterization of the anti-TMEM216 rabbitpolyclonal antiserum: FIG. 11(a) illustrates an Immunoblotting of ca. 10μg whole cell extracts (WCEs) with affinity-purified anti-TMEM216 (leftpanel) and the corresponding pre-immune (right panel), both at ×1000titers. Immunodetection revealed two major protein isoforms of sizes 27and 19 kD with anti-TMEM216 but not the preimmune (60 s exposure time).WCEs: 1 & 2, normal control fibroblasts; 3, HEK293; 4 & 5 IMCD3 (earlyand late passage). FIG. 1(b) illustrates Co-immunostaining andepifluorescence microscopy of post-confluent, ciliated IMCD3 cellmonolayers with pre-immune and anti-TMEM216 sera (green, as indicated).Primary cilia were co-stained for acetylated-a-tubulin (red) and nucleiwere stained with DAPI (blue). Endogenous TMEM216 co-localizes withprimary cilia (middle panels; arrows), which is a staining patternpartially abrogated by treatment of affinity-purified TMEM216 with 50mg/ml cognate peptide (peptide block control; bottom panels). FIG. 11(c)illustrates Immunostaining of human kidney with TMEM216 ab (left)compared with preimmune serum, both at 1:200 dilution. Visible aredark-stained developing glomerular capsules in the renal cortex.

FIG. 12 illustrates Localization of epitope-tagged TMEM126: illustratesCo-immunostaining and confocal microscopy of post-confluent, ciliatedIMCD3 cell monolayers transfected with mCherryRed-TMEM216 (red; toppanels) and TMEM216-FLAG (red; bottom panels). Primary cilia wereco-stained for acetylated-a-tubulin (green). DAPI staining of nuclei isshown in blue. Epitope-tagged TMEM216 co-localizes with primary cilia(arrows), shown in detail in the insets, and the mitotic spindle of acell in late telophase (bottom panel). Bars=5 um.

FIG. 13 illustrates Localization of Dvl1 following Tmem216 knockdown.IMCD3 cells were fixed at subconfluence and stained for γ-tubulin andDvl1. There was no notable difference in localization of Dvl1 in thepresence or absence of Tmem216 siRNAs. Scale bar 10 um.

FIG. 14 illustrates RT-PCR analysis of effectiveness of Tmem216 siRNA.Tmem216 was amplified for various cycles from IMCD3 cells (−ve: absentreverse transcriptase). Tmem216 was detectable following scrambledsiRNA, but not readily detectable following Tmem216 siRNA1. M=laddermarker, Hprt gene was used as a positive amplification control.

FIG. 15A-J illustrate full scans of Western blot data generated asdiscussed above.

The drawings set forth herein are illustrative of embodiments of theinvention and are not meant to limit the scope of the invention asencompassed by the claims. Like reference symbols in the variousdrawings indicate like elements.

Reference will now be made in detail to various exemplary embodiments ofthe invention, examples of which are illustrated in the accompanyingdrawings. The following detailed description is provided to give thereader a better understanding of certain details of aspects andembodiments of the invention, and should not be interpreted as alimitation on the scope of the invention.

DETAILED DESCRIPTION

In alternative embodiments, the invention provides compositions andmethods for the identification of genetic polymorphic variations in thehuman TMEM216 gene, and methods of using the identified geneticpolymorphisms. In alternative embodiments, the invention providesisolated, synthetic or recombinant polypeptides that are human TMEM216variants, and nucleic acids encoding these human TMEM216 variantproteins.

Abbreviations and Definitions

To facilitate understanding of the invention, a number of terms andabbreviations as used in alternative embodiments are defined as follows:

In alternative embodiments, the terms “genetic variant,” “mutation,” and“nucleotide variant” are used herein interchangeably to refer to changesor alterations to a reference TMEM216 gene sequence at a particularlocus, including, but not limited to, nucleotide base deletions,insertions, inversions, and substitutions in the coding and noncodingregions. Deletions may be of a single nucleotide, a portion or a regionof the nucleotide sequence of the gene, or of the entire gene sequence.Insertions may be of one or more nucleotides. The genetic variants mayoccur in transcriptional regulatory regions, untranslated regions ofmRNA, exons, introns, or exon/intron junctions. The genetic variants mayor may not result in stop codons, frame shifts, deletion of amino acids,altered amino acid sequence, or altered protein expression level. Themutations or genetic variants can be somatic, i.e., occur only incertain tissues of the body and are not inherited in the germline, orgermline mutations, i.e., inherited mutations found in all tissues.

In alternative embodiments, “Genetic polymorphism” as used herein refersto the phenomena that two or more genetic variants in a particular locusof a gene are found in a population.

In alternative embodiments, the term “allele” or “gene allele” is usedherein to refer generally to a naturally occurring gene having thereference sequence or a gene containing a specific genetic variant.

In alternative embodiments, the term “TMEM216 nucleic acid” means anucleic acid molecule the nucleotide sequence of which is found uniquelyin a TMEM216 gene or a substantially equivalent form thereof. That is,the nucleotide sequence of a “TMEM216 nucleic acid” can be a full-lengthsequence of, or a portion found in, either TMEM216 genomic DNA ormRNA/cDNA, either wild-type or naturally existing variant TMEM216 gene,or an artificial nucleotide sequence encoding a wild-type TMEM216protein or naturally existing polymorphic variant TMEM216 protein.

In alternative embodiments, the term “TMEM216 nucleic acid variant”refers to a naturally occurring TMEM216 nucleic acid.

In alternative embodiments, the term “amino acid variant” refers toamino acid changes to a reference TMEM216 protein sequence resultingfrom nucleotide variants or mutations to the reference gene encoding thereference TMEM216 protein. The term “amino acid variant” is intended toencompass not only single amino acid substitutions, but also amino aciddeletions, insertions, and other changes of amino acid sequence in aTMEM216 protein that can indicate a susceptibility to Joubert Syndromeor other ciliopathies.

In alternative embodiments, the term “TMEM216 protein variant” is usedherein relative to a reference TMEM216 protein to mean a TMEM216 proteinfound in a population that is the coding product of a TMEM216 geneallele containing genetic variants such as single nucleotidesubstitutions, insertions, deletions, and DNA rearrangements, which leadto alterations in the protein sequence of the protein variant.

In alternative embodiments, the term “locus” refers to a specificposition or site in a nucleotide sequence of a gene, or amino acidsequence of a protein. Thus, there may be one or more contiguousnucleotides in a particular gene locus, or one or more amino acids at aparticular locus in a polypeptide. Moreover, “locus” may also be used torefer to a particular position in a gene sequence where one or morenucleotides have been deleted, inserted, or inverted.

In alternative embodiments, the terms “polypeptide,” “protein,” and“peptide” are used herein interchangeably to refer to amino acid chainsin which the amino acid residues are linked by peptide bonds or modifiedpeptide bonds. The amino acid chains can be of any length of greaterthan two amino acids. Unless otherwise specified, the terms“polypeptide,” “protein,” and “peptide” also encompass various modifiedforms thereof. Such modified forms may be naturally occurring modifiedforms or chemically modified forms. Examples of modified forms include,but are not limited to, glycosylated forms, phosphorylated forms,myristoylated forms, palmitoylated forms, ribosylated forms, acetylatedforms, and the like. Modifications also include intra-molecularcrosslinking and covalent attachment of various moieties such as lipids,flavin, biotin, polyethylene glycol or derivatives thereof, and thelike. In addition, modifications may also include cyclization, branchingand cross-linking. Further, amino acids other than the conventionaltwenty amino acids encoded by genes may also be included in apolypeptide.

In alternative embodiments, the terms “primer,” “probe,” and“oligonucleotide” may be used herein interchangeably to refer to arelatively short nucleic acid fragment or sequence. They can be DNA,RNA, or a hybrid thereof, or chemically modified analogs or derivativesthereof. Typically, they are single-stranded. However, they can also bedouble-stranded having two complementing strands that can be separatedapart by denaturation. In certain aspects, they are of a length of fromabout 8 nucleotides to about 200 nucleotides, preferably from about 12nucleotides to about 100 nucleotides, and more preferably about 18 toabout 50 nucleotides. They can be labeled with detectable markers ormodified in any conventional manners for various molecular biologicalapplications.

In alternative embodiments, the term “isolated,” when used in referenceto nucleic acids (which include gene sequences or fragments) of thisinvention, is intended to mean that a nucleic acid molecule is presentin a form other than found in nature in its original environment withrespect to its association with other molecules. For example, since anaturally existing chromosome includes a long nucleic acid sequence, an“isolated nucleic acid” as used herein means a nucleic acid moleculehaving only a portion of the nucleic acid sequence in the chromosome butnot one or more other portions present on the same chromosome. Thus, forexample, an isolated gene typically includes no more than 25 kb ofnaturally occurring nucleic acid sequence which immediately flanks thegene in the naturally existing chromosome or genomic DNA. However, it isnoted that an “isolated nucleic acid” as used herein is distinct from aclone in a conventional library such as genomic DNA library and cDNAlibrary in that the clones in a library are still in admixture withalmost all the other nucleic acids in a chromosome or a cell. Inalternative embodiments, a nucleic acid of the invention can be in avector, a plasmid, an expression vector and the like.

In alternative embodiments, the term “isolated nucleic acid” comprises“purified nucleic acid” which means a specified nucleic acid is in asubstantially homogenous preparation of nucleic acid substantially freeof other cellular components, other nucleic acids, viral materials, orculture medium, or chemical precursors or by-products associated withchemical reactions for chemical synthesis of nucleic acids. A “purifiednucleic acid” can be obtained by standard nucleic acid purificationmethods. In alternative embodiments, for a purified nucleic acid, thespecified nucleic acid molecule constitutes at least 15 percent of thetotal nucleic acids in the preparation. The term “purified nucleic acid”also means nucleic acids prepared from a recombinant host cell (in whichthe nucleic acids have been recombinantly amplified and/or expressed),or chemically synthesized nucleic acids.

In alternative embodiments, the term “isolated nucleic acid” alsoencompasses a “recombinant nucleic acid” which is used herein to mean ahybrid nucleic acid produced by recombinant DNA technology having thespecified nucleic acid molecule covalently linked to one or more nucleicacid molecules that are not the nucleic acids naturally flanking thespecified nucleic acid. Typically, such nucleic acid molecules flankingthe specified nucleic acid are no more than 50 kb. In addition, thespecified nucleic acid may have a nucleotide sequence that is identicalto a naturally occurring nucleic acid, or a modified form, or mutantform thereof having one or more mutations such as nucleotidesubstitution, deletion/insertion, inversion, and the like.

In alternative embodiments, “isolated nucleic acid” further includes achemically synthesized nucleic acid having a naturally occurringnucleotide sequence or an artificially modified form thereof (e.g.,dideoxy forms).

In alternative embodiments, the term “isolated polypeptide” means apolypeptide molecule is present in a form other than found in nature inits original environment with respect to its association with othermolecules. The term “isolated polypeptide” encompasses a “purifiedpolypeptide” which is used herein to mean that a specified polypeptideis in a substantially homogenous preparation, substantially free ofother cellular components, other polypeptides, viral materials, orculture medium, or when the polypeptide is chemically synthesized,substantially free of chemical precursors or by-products associated withthe chemical synthesis. For a purified polypeptide, preferably thespecified polypeptide molecule constitutes at least 15 percent of thetotal polypeptide in the preparation. A “purified polypeptide” can beobtained from natural or recombinant host cells by standard purificationtechniques, or by chemical synthesis.

In alternative embodiments, the term “isolated polypeptide” alsoencompasses a “recombinant polypeptide,” which is used herein to mean ahybrid polypeptide produced by recombinant DNA technology or chemicalsynthesis having a specified polypeptide molecule covalently linked toone or more polypeptide molecules which do not naturally link to thespecified polypeptide.

In alternative embodiments, “haplotype” is a combination of genetic(nucleotide) variants in a region of an mRNA or a genomic DNA on achromosome found in an individual. Thus, a haplotype includes a numberof genetically linked polymorphic variants that are typically inheritedtogether as a unit.

In alternative embodiments, the term “reference sequence” refers to apolynucleotide or polypeptide sequence known in the art, including thosedisclosed in publicly accessible databases (e.g., GenBank), or a newlyidentified gene sequence, used simply as a reference with respect to thevariants provided in the invention. The nucleotide or amino acidsequence in a reference sequence is contrasted to the alleles disclosedin the invention having newly discovered nucleotide or amino acidvariants.

Genetic Polymorphic Variations in the TMEM216 Gene

The invention is based on the discovery of a number of polymorphisms inhuman Transmembrane Protein 216 (“TMEM216”), a gene identified on thebasis of its genetic linkage to Joubert Syndrome and Related Disorders(JSRD) and Meckel Syndrome (MKS), particularly in the Ashkenazi Jewishpopulation. A detailed description of the newly discovered polymorphismsis provided in Table 1, below (for example, c.G218T; p.R73L).

These polymorphisms are believed to be deleterious and cause significantalterations in structure or biochemical activities in the TMEM216 geneproducts expressed from mutant TMEM216 genes. Patients with suchpolymorphisms in one of their TMEM216 genes are predisposed to, and thushave a significantly increased likelihood of, having JSRD and MKS: orhave one of these conditions. Therefore, the polymorphisms of thisinvention are useful in genetic testing as markers for the prediction ofpredisposition to ciliopathies, including JSRD and MKS.

The inventors discovered that the great majority, if not all, AshenaziJewish patients with Joubert syndrome share a common mutation (c.G218T;p.R73L) in this new gene TMEM216. Of 12 Jewish families tested, 100% ofthe patients were homozygous for the G218T mutation. These familiesexhibit phenotypically the classical form of Joubert Syndrome (whichincludes the neuroradiological hallmark molar tooth image (MTI),hypotonia, mental retardation, abnormal breathing and ocular motorapraxia). Additionally, retinal involvement was seen in 25% of Jewishpatients and kidney involvement was seen in 17% of Jewish patients. Thismakes it possible to perform genetic testing in this population veryeasily. Other mutations at the R73 amino acid account for disease inother isolated populations, e.g., R73L. R73H and R73C.

In alternative embodiments, the invention provides 4 major spliceisoforms, the longest and most prevalent encoding a protein of 148 aminoacid (aa) (SEQ ID NO: 1); encoded by an RNA structure having a sequenceSEQ ID NO:3, which is considered to be the full-length mRNA. TMEM216genomic organization is schematically illustrated in FIG. 2 b.

In FIGS. 2i and 2j , the arrows are pointing to the location of theTMEM216 protein inside of culture cells. The protein is found toco-localize with known markers of cilia, including the Ac alpha-tubulinand the GT335 proteins. This data is generated using antibodies toreport the localization of the proteins of interest. The antibodiesreact to the protein of interest in the cell and are labeled with afluorescent color so that the protein of interest can be detected underthe microscope.

TABLE 1 Clinical and molecular data of TMEM216 mutated families. Familydata Genetic data Age Clinical data Nucleotide Protein Fam (sex) OriginCNS Eye Kidney Liver Other changes alterations Joubert syndrome relateddisorders COR000 11y, M Italian MTS — NPH ELE — 218G > T R73L 15y, F —NPH — 20y, F — NPH — 29y, M — NPH — COR284 22y, F Italian MTS NPH 218G >T R73L COR114 1m, M Turkish MTS MicroC N/A N/A PD 218G > A R73H 13w, MEc CK BDP PD, BLB F401 N/A New MTS + NPH N/A N/A 217C > T R73C Zealand398T > G L133X COR076 1y, F Ashk MTS, PMG — ToF 218G > T R73L fetus —COR287 3m, M Ashk MTS PD 218G > T R73L MTI005 13y, M Euro MTS OMA NPH? —CD 218G > T R73L 3y, F MTS OMA — CD MTI161 4y, M Ashk MTS OMA, Nys — —PD, TT, MP 218G > T R73L MTI214 4y, F Ashk MTS OMA — — CMD 218G > T R73LMTI467 fetus Ashk MTS, N/AA — — PD, MOF 218G > T R73L DWM CD, HYPTMTI585 1y, F Ashk MTS Co ACMD — CMD 218G > T R73L MTI658 8y, F Ashk MTSNys NPH? — PD, CMD 218G > T R73L 5y, F MTS Nys NPH? — PD, CMD 2 fetusesN/A PD MTI1006 9y, M Ashk MTS OMA, Nys, — — — 218G > T R73L 1y, M2 MTSOMA, Nys, — — PD (cousin) MTI1008 4y, F Ashk MTS, OMA N/A N/A RTP 218G >T R73L DWM Meckel syndrome F002 MKS15 21w, M Tunisian Mc CK BDP PD, CP,BLB 341T > G L114R MKS16 14w, F An CK BDP PD, BLB F005 MKS74 24w, MTunisian Mc MicroO CK BDP PD, CP, IUGR, 341T > G L114R BLB, HypoG F56MKS491 N/A Palestinian An CK N/A 230G > C G77A→splice: MKS492 15w DW, EcCK N/A IUGR T78KfsX30 F58 MKS511 SB, M Palestinian Ec CK BDP PD, CP230G > C G77A→splice: MKS512 N/A Ec CK BDP PD T78KfsX30 F154 MKS107722wSB Palestinian Mc CK N/A 230G > C G77A→splice: T78KfsX30 A2423 16221w, M British Ec — CK BDP PD, CP, VSD, IM, BLB 253C > T R85X 163 12w, MEc — CK — CH, Omph Legend: ACMD: abnormal cortico-medullarydifferentiation; An: anencephaly; Ashk: Ashkenazi Jewish; BDP: bileducts proliferation; BLB: bowing of long bones; CD: clinodactyly; CH:cystic hygroma; CK: cystic kidneys; CMD: camptodactyly; Co:chorioretinal coloboma; CP: cleft palate; CVA: cerebellar vermisagenesis; DW: Dandy-Walker malformation; Ec: encephalocele; ELE:elevated liver enzymes; Euro: European; F: female; HypoG: hypoplasticexternal genitalia; HYPT: hypertelorism; IM: intestinal malrotation;IUGR: intrauterine growth retardation; M: male; m: months; IUGR:intrauterine growth retardation; Mc: meningocele; MEc:meningoencephalocele; MOF: multiple oral frenulae; MicroC: microcornea;MicroO: microphthalmia; MP: micropenis; MTS: molar tooth sign; N/A: notavailable; NPH: nephronophthisis; Nys: nystagmus; OMA: oculomotorapraxia; Omph: omphalocele; PD: polydactyly; PMG: polymicrogyria; RTP:rhythmic tongue protrusions; SB: stillbirth; ToF: tetralogy of Fallot;TT: tongue tumors; VSD: ventricular septal defect; w: gestational weeks;y: years.

TABLE 1 Clinical and molecular data of TMEM216 mutated families. Familydata Genetic data Age Clinical data Nucleotide Protein Fam (sex) OriginCNS Eye Kidney Liver Other changes alterations Joubert syndrome relateddisorders COR000 11y, M Italian MTS — NPH ELE — 218G > T R73L 15y, F —NPH — 20y, F — NPH — 29y, M — NPH — COR284 22y, F Italian MTS NPH 218G >T R73L COR114 1m, M Turkish MTS MicroC N/A N/A PD 218G > A R73H MKS35013gw, M Ec CK BDP PD, BLB F401 N/A New MTS + NPH N/A N/A 217C > T R73CZealand 398T > G L133X COR076 1y, F Ashk MTS, PMG — ToF 218G > T R73Lfetus — COR287 3m, M Ashk MTS PD 218G > T R73L MTI005 13y, M Euro MTSOMA NPH? — CD 218G > T R73L 3y, F MTS OMA — CD MTI161 4y, M Ashk MTSOMA, Nys — — PD, TT, MP 218G > T R73L MTI214 4y, F Ashk MTS OMA — — CMD218G > T R73L MTI467 fetus Ashk MTS, N/AA — — PD, MOF 218G > T R73L DWMCD, HYPT MTI585 1y, F Ashk MTS Co ACMD — CMD 218G > T R73L MTI658 8y, FAshk MTS Nys NPH? — PD, CMD 218G > T R73L 5y, F MTS Nys NPH? — PD, CMD 2fetuses N/A PD MTI1006 9y, M Ashk MTS OMA, Nys, — — — 218G > T R73L 1y,M2 MTS OMA, Nys, — — PD (cousin) MTI1008 4y, F Ashk MTS, OMA N/A N/A RTP218G > T R73L DWM Meckel syndrome F002 MKS15 21gw, M Tunisian Mc CK BDPPD, CP, BLB 341T > G L114R MKS16 14gw, F An CK BDP PD, BLB F005 MKS7424gw, M Tunisian Mc MicroO CK BDP PD, CP, IUGR, 341T > G L114R BLB,HypoG F56 MKS491 N/A Palestinian An CK N/A 230G > C G77A→splice: MKS49215gw DW, Ec CK N/A IUGR T78KfsX30 F58 MKS511 SB, M Palestinian Ec CK BDPPD, CP 230G > C G77A→splice: MKS512 N/A Ec CK BDP PD T78KfsX30 F154MKS1077 22gw Palestinian Mc CK N/A 230G > C G77A→splice: T78KfsX30 A2423162 21gw, M British Ec — CK BDP PD, CP, VSD, IM, BLB 253C > T R85X 16312gw, M Ec — CK — CH Legend: ACMD: abnormal cortico-medullarydifferentiation; An: anencephaly; Ashk: Ashkenazi Jewish; BDP: bileducts proliferation; BLB: bowing of long bones; CD: clinodactyly; CH:cystic hygroma; CK: cystic kidneys; CMD: camptodactyly; Co:chorioretinal coloboma; CP: cleft palate; CVA: cerebellar vermisagenesis; DW: Dandy-Walker malformation; Ec: encephalocele; ELE:elevated liver enzymes; Euro: European; F: female; HypoG: hypoplasticexternal genitalia; HYPT: hypertelorism; IM: intestinal malrotation;IUGR: intrauterine growth retardation; M: male; m: months; IUGR:intrauterine growth retardation; Mc: meningocele; MEc:meningoencephalocele; MOF: multiple oral frenulae; MicroC: microcornea;MicroO: microphthalmia; MP: micropenis; MTS: molar tooth sign; N/A: notavailable; NPH: nephronophthisis; Nys: nystagmus; OMA: oculomotorapraxia; PD: polydactyly; PMG: polymicrogyria; RTP: rhythmic tongueprotrusions; SB: stillbirth; ToF: tetralogy of Fallot; TT: tonguetumors; VSD: ventricular septal defect; gw: gestational weeks; y: years.Nucleotide and Amino Acid Variants Tetraspan transmembrane proteins arecharacterized by four hydrophobic, putative transmembrane domains(TM1-TM4), forming two extracellular and one intracellular loop, whichregulate signaling and trafficking properties of their partner proteinsin multiple cellular contexts¹. While little is known about theirfunction, they can act with Wnt receptors², and their ability to formcomplexes with a wide variety of membrane and cytosolic proteins³,suggests that they may participate in the formation of membrane domainsthat regulate signaling and sorting processes.

The neurological features of JSRD include hypotonia, ataxia, psychomotordelay, irregular breathing pattern and oculomotor apraxia and arevariably associated with multiorgan involvement, mainly retinaldystrophy, nephronophthisis (NPH) and congenital liver fibrosis. JSRDare genetically heterogeneous, and all known genes encode for proteinslocalized at or near the primary cilium⁴. The JBTS2 (also known asCORS2) locus was mapped to chromosome 11p12-q13.3 in a large Sicilianfamily and in three consanguineous pedigrees from the Middle East^(5,6).Aligning the two datasets suggested a minimal candidate interval betweenD11S1344 and D11S1883 (46.123-63.130 Mb) 7 (FIG. 1a ).

In addition to occipital encephalocele, MKS patients display otherposterior fossa defects, cystic dysplastic kidneys, hepatic bile ductproliferation, and polydactyly, which overlap with JSRD, and the twoconditions are known to be allelic at four loci⁸⁻¹¹. The MKS2 locus wasinitially mapped in families of North African and Middle Easternancestry chromosome 11q to a region telomeric to JBTS2¹², but oursubsequent identification of additional families, as well as SNPre-analysis of the initial families indicated allelism with JBTS2between rs 113480 and rs953894 (48.014-62.518 Mb). (FIG. 6). BecauseJSRD and MKS are considered ciliopathies, of the 200 total candidategenes, the exons and splice sites of genes listed in the cilia proteomedatabases¹³⁻¹⁴ were sequenced from one affected from each JBTS2/MKS2family, but no mutations were identified.

Transmembrane proteins also represented attractive candidates, due tosimilarities to MKS3′TMEM67 encoding Meckelin, which is mutated both inJSRD and MKS^(8,15). Therefore the eight genes encoding transmembraneproteins were sequenced, eventually identifying homozygous deleteriousmutations in TMEM216 in six of the 12 JSRD/MKS families compatible withlinkage to the locus. The residue p.R73 was mutated both in the Sicilianfamily with JSRD (COR00, p.R73L) and in a Turkish family, in which MKSand JSRD coexisted in the same sibship (COR114, p.R73H). Two Tunisianfamilies, not known to be related (F002, F005), carried the same p.L114Rmutation, and two Palestinian families (F56, F58) carried the samep.G77A mutation. The p.G77A mutation resulted from a substitution(c.230G>C) affecting the first base of exon 5, thus possibly alteringsplicing. RT-PCR confirmed defective splicing (FIG. 7), leading to useof an alternative splice site in intron 4, the inclusion of anadditional 46 bp and resultant premature protein termination(p.T78KfsX30). No mutations were identified in ethnically matchedcohorts. These include 227 Italian and 109 Turkish (all wildtype atp.R73), 158 Palestinian and 112 Tunisian individuals, (all wildtype atp.G77 and p.L114). Additionally, all mutations were screened in 200Central Asian (predominantly Pakistani), 200 European (predominantlyBritish), as well as a cohort of 96 ethnically diverse individuals.

An additional 460 JSRD and 132 MKS probands were screened and mutationswere identified in 12 and 2 further cases, respectively. Interestingly,11 of 12 JSRD families shared the same homozvgous p.R73L mutation, ofwhich one family was also from Sicily and ten were of Ashkenazi Jewishdescent. Additionally, a JSRD family from New Zealand was compoundheterozygous for the missense change p.R73C and the truncating mutationp.L133X. Of the two mutated MKS families, one Palestinian family wasalso homozygous for the same splice site mutation p.G77A (T78KfsX30);and one British family with no known consanguinity had two affectedfetuses carrying the homozygous truncating mutation p.R85X. Saturationof the region surrounding the p.R73L mutation with 17 SNP/microsatellitemarkers indicated that the Ashkenazi Jewish and the Sicilian familiesshared the same ancestral haplotype, spanning 472 Kb around the mutation(FIG. 8), and could be dated back at least 20 generations.Microsatellite analysis also detected shared haplotypes in the twoPalestinian (F56, F58) and in the two Tunisian families (F002, F005),homozygous for the same mutations (FIG. 6).

Overall, 21 JSRD patients from 14 families and 10 MKS fetuses from 6families carried TMEM216 mutations (FIG. 1b , Table 1). Among JSRD, thephenotype was characterized by frequent occurrence of NPH (9/21) andpolvdactyly (9/21), while retinal dystrophy and congenital hepaticfibrosis were never observed. In keeping with this, sequence analysis of96 patients with Bardet-Biedl syndrome identified no mutations, sinceretinopathy is a key feature of this disease. However, two heterozygouschanges p.L28F and p.R54C were identified, which were absent from 386control chromosomes and were predicted to be evolutionarily intolerant,suggesting that TMEM216 might contribute epistatic alleles to BBS in afashion similar to what has been observed for other MKS loci¹⁶. Of note,in two JS patients (MTI161 and MTI467) the polydactyly was associatedwith either tongue tumors or multiple oral frenula, corresponding to theOro-Facio-Digital type VI (or Varadi-Papp) syndrome¹⁷ (OMIM %277170),indicating that TMEM216 is the first known identified cause. In the 10MKS fetuses with TMEM216 mutations, distinctive clinical features wereskeletal dysplasia, including intrauterine growth retardation or bowingof the long bones in 7/11 fetuses, cleft palate in 4/11, and anencephalyin 2/11 (Table 1, FIG. 9), suggesting extreme pleiotrophic expressivity.Missense mutations predominated in JSRD patients whereas truncating orsplice mutations predominated in MKS patients, suggesting that partiallyinactive but not null mutations may be compatible with survival.

All of the nonsynonymous changes occurred in evolutionarily conservedresidues (FIG. 1c-d ), and led to unstable protein when transfected intoheterologous cells (FIG. 1e , FIG. 10). Although truncating mutationswere identified in both the middle and end of the protein, p.R73transversions predominated (FIG. 1c ), with the p.R73L clearly a foundermutation. The carrier frequency in the Ashkenazi population wasdetermined to be about 1:100, as two heterozygous healthy unrelatedcarrier individuals were identified among a screened cohort of 212Ashkenazi individuals, making carrier detection possible at least inthis population.

TMEM216 is a poorly annotated gene, with RefSeq predicting a protein ofjust 86 aa, suggesting potential alternative splicing. To characterizethis mRNA Northern analysis was performed with a commercial human fetalblot, and found a single major mature isoform at about 1.4 Kb (FIG. 2a), agreeing with the predicted 1.3 Kb of the longest representativecDNAs. To interrogate splicing primers complementary to the furthest 5′and 3′ regions of the known cDNA were designed, and sequenced 48 clonedPCR products from a 20 week gestation human fetal brain library. Fourmajor splice isoforms were identified, the longest and most prevalentpredicting a protein of 148 as (FIG. 2b ), which is considered to be thefull-length mRNA. There is a cryptic splice donor site in exon 1, which,when spliced to exon 3 (15.6%0/of clones) leads to a 30 aa protein.Furthermore, a cryptic exon 2 is spliced into the mature mRNA in over30% of the recovered clones, but these two resultant mRNAs predictproteins of only 34 or 25 aa. Thus, there is extensive alternativesplicing in relevant tissue, encoding for very short proteins, thefunctions of which were not evaluated further. No mutations were foundin any of these cryptic coding regions.

TMEM216 contains a transmembrane 17 superfamily domain, also containedin TMEM17 and TMEM80, the only two proteins with similar homology. Basedon this sequence similarity, mutations were tested in the predicted fulllength TMEM17 and TMEM80 genes among a cohort of 96 JS patients and 60MKS patients, but found no mutations, suggesting a unique role ofTMEM216 in these diseases.

To elucidate potential physiological roles for TMEM216 in humandevelopment, its expression was examined in human embryonic tissues. Insitu hybridization analysis in human embryos confirmed its ubiquitousexpression (FIG. 2c-h ) and may help explain the multi-organ involvementobserved in these patients. In particular, expression was observed inthe central nervous system, limb bud, kidney and cartilage, which issimilar to the broad and relatively low-level expression pattern ofother JSRD/MKS genes. An anti-TMEM216 polyclonal affinity-purifiedantibody was raised against amino acids 81-90, demonstrated specificity(FIG. 11), and immunostained two different ciliated cell lines(intramedullary collecting duct [IMCD3] and retinal pigment epithelium[hRPE]), used widely to study ciliary biology. Partial overlappinglocalization was observed with the primary cilium or adjacent basal bodyin the majority of cells, as marked by either acetylated or glutamylatedtubulin staining (FIG. 2i-j ), which was blocked by preincubation withthe TMEM216 peptide (FIG. 11b , Supplemental FIG. 6b ). TMEM216 antibodyalso reacted strongly in organs like fetal kidney containing ciliatedcells (FIG. 11c , Supplemental FIG. 6c ). Epitope tagged TMEM216 showedsimilar but more diffuse localization to cilia and other microtubulestructures (i.e. mitotic spindle in cells undergoing late telophase,FIG. 12), suggesting TMEM216 may exert its effect on both cilia andother microtubule-based structures.

In hTERT-immortalized fetal TMEM216 p.R85X homozygous mutantfibroblasts, a failure in ciliogenesis was noticed following 48 hr serumstarvation (FIG. 3a ) compared with controls. Acetylated microtubules inTMEM216-mutated fibroblasts also appeared disorganized. Western analysisof whole cell lysates from control fibroblasts identified two majorTMEM216 isoforms of 19 and 27 kD (FIG. 3b ) with the 19 kD band matchingthe predicted 148 as full length protein. No cDNAs were identifiedencoding a 27 kD protein despite comprehensive attempts to extend theORF, and both were lost or attenuated (most notably the 19 kD isoform)in TMEM216 p.R85X fibroblasts from fetus 162, or following siRNAknockdown. Therefore transient transfection of monolayers was performedof the mouse ciliated cell line IMCD3 with two separate Tmem216 siRNAduplexes. Tmem216 knockdown prevented ciliogenesis in polarized cells,and blocked correct docking of centrosomes at the apical cell surface(FIG. 3c ), as seen previously for Meckelin and MKS 1¹⁸. These data werequantified by analyzing the percent of cells with clearly evident cilia(defined as >1 um length) vs. those without cilia (defined as <1 umlength), and by analyzing the percent of cells with apically positionedcentrosomes (defined as the centrosome located apical to the nucleus).In cells in which Tmem216 was knocked down, striking defect was observedin both of these measurements compared with two separate control lines(FIG. 3d-e , chi-squared test, p<0.001, for 350 cells from eachcondition).

The similarities in cellular phenotypes of Mks3 and Tmem216 knockdown,and subcellular localizations of Meckelin and TMEM216, then prompted usto ask if the two proteins could interact. Lysates of cell transfectedwith GFP-tagged TMEM216 were immunoprecipitated with antibodies toeither N- or C-terminal portions of Meckelin compared with negativecontrols, and then analyzed by Western for the presence of TMEM216. Acomplex between TMEM216 and Meckelin was observed using this assay (FIG.4a ). The complementary experiment was performed by immunoprecipitatingthe same lysates with GFP antibody compared with negative controls, andthen analyzed by Western for the presence of Meckelin. No evidence ofthis complex was found (FIG. 4b ), suggesting that TMEM216 can complexwith Meckelin in cells.

Many aspects of actin-dependent polarized cell behavior, includingmorphogenetic cell movements¹⁹ and ciliogenesis²⁰ are mediated by theplanar cell polarity (PCP) pathway of non-canonical Wnt signaling²¹.Therefore RhoA was first examined, since the Rho family of small GTPasesare key mediators of this pathway^(21,22). Consistent with previousresults for MKS3 patient fibroblasts or knockdown²³, it was found thatRhoA signaling was hyperactive in both TMEM216 p.R85X fibroblasts orfollowing Tmem216 knockdown (FIG. 4c-d ), despite normal total amountsof RhoA in these cells. Since centrosome docking at the apical cellsurface is prevented by the interruption of actin remodeling²⁴, and isdependent on both RhoA activation and regulation by the core PCP proteinDishevelled (Dvl)²⁵, it was therefore confirmed that RhoA is localizedto the basal body in confluent IMCD3 cells (FIG. 4e ). This result isconsistent with previous findings that RhoA co-localizes with most basalbodies in multi-ciliated cells²⁵. However, following Tmem216 knockdownfor 24 hr, RhoA was mislocalized to peripheral regions of the basal bodyand to basolateral cell-cell contacts (FIG. 4e ), consistent withtranslocation of ectopically-activated RhoA to the cytosol²⁶. Tmem216knockdown also showed evidence of a mislocalization of γ-tubulin at thecentrosomei asal body for this timepoint, which suggests a defect inγ-tubulin nucleation, one of the earliest steps in ciliogenesis²⁷.Mislocalization was not apparent at later timepoints (72 hr) inpost-confluent cells. The established role of RhoA in modulating theactin cytoskeleton in the PCP pathway then led us to evaluate MKS2patient fibroblast lines for alterations. A co-localization of actinstress fibers and the actin cross-linker filamin-A in the cytoplasm ofthese mutant cells was found, which was absent in control (FIG. 4f ).

Dvl signaling in cells was looked at, since cilia negatively regulateDvl activation²⁸, and Dvl mediates Rho activation at the apical surfaceof ciliated epithelial cells²⁵. It was found that loss of TMEM216 (inboth TMEM216 mutated cells and following Tmem216 knockdown) causedconstitutive phosphorylation of Dvl1 (FIG. 5a , left panel), implyingthat TMEM216 modulates hyperresponsiveness of signaling pathwaysmediated by Dvl and RhoA. It was found that Rho inhibition alsoincreased the Dvl1 phosphorylation in ciliated cells, implying theexistence of feedback mechanism between Rho and Dvl (FIG. 5a , rightpanel). Unexpectedly, the constitutive Dvl1 phosphorylation associatedwith TMEM216 knockdown was blocked by Rho inhibition (FIG. 5a , rightpanel), suggesting that the loss of TMEM216 in ciliated cells can modifythis feedback mechanism. Although this possibility warrants furtherinvestigation, our data nevertheless suggests a working model in whichDvl1, RhoA and TMEM216 may serve as part of a complex in thepericentrosomal compartment to mediate cellular polarization andcentrosomal apical docking, and in support of this hypothesis, previousstudies have shown that Dvl and Rho contribute to a core framework forregulating the apical docking of centrosomes²⁵. Furthermore, it wasobserved evidence of a common complex containing TMEM216, Dvl1 and RhoAin TMEM216-transfected cells (FIG. 5b ), and because there was nodifference in the localization of Dvl1 following Tmem216 knockdown, thisdata predicts that the hyperactivation of Rho in the absence of TMEM216might be responsible for the centrosome docking defect at the apicalcellular surface. As expected, it was found that the impaired centrosomedocking that was observed following Tmem216 knockdown was rescued in adose-dependent fashion the using Rho inhibitor (FIG. 5c ). High levelsof this inhibitor (>2 ug/ml) impaired centrosome docking in normalsiRNA-untreated IMCD3 cells, consistent with previous findings²⁴ (datanot shown).

Meckelin is proposed to regulate centrosomal docking through the RhoAsignaling pathway²³, and bears similarity to the Frizzled family oftransmembrane Wnt receptors 15. Direct evidence of a role for Meckelinin PCP signaling stems from zebrafish embryo morphant phenotypesfollowing morpholino knock-down of mks3²⁹. These included defects ingastrulation movement (a shortened body axis, broad notochords andmisshapen somites), which are typical of defects in non-canonical (PCP)Wnt signaling, and which have been observed in numerous ciliary andbasal body morphants^(29,30). Strikingly similar phenotypes ciliaryphenotypes was seen in tmem216 morphants, which are largely rescued byRNA encoding human TMEM216 (FIG. 5d ), and fully rescued by RNA encodingnontargetable zebrafish tmem216 (not shown). Therefore the tmem216 andmks3 morphant phenotypes in zebrafish were compared, and noted similardefects in both live embryos and in embryros in which pronephricmesoderm, anterior neural structures, adaxial mesodermal cells, andsomites were labeled with a krox20, pax2, and myoD riboprobe cocktail(FIG. 5e-f ). Quantification (FIG. 5(g)) demonstrated alteration ofconvergence to the midline and extension along the AP axis consistentwith a PCP defect, although the AP extension defect was more pronouncedin the mks3 compared to the tmem216 morphant.

Recent work has implicated the tetraspanin TSPAN12 in the regulation ofNorrin signaling by the Wnt receptor Frizzled-4 and coreceptor LRP5².Therefore, without being bound by a particular theory, it is believedthat TMEM216, a novel tetraspan protein, forms a non-canonical Wntreceptor-coreceptor complex with Meckelin. Our data supports a role forboth proteins in mediating PCP signaling through the RhoA pathway tocause actin cytoskeleton rearrangements, although whether Rho functionsupstream or downstream of Dvl1 remains to be determined. In apicalregions of the cell, such actin reorganization would be an essentialstep before the centrosome/basal body could dock correctly and initiateciliogenesis. The identification of mutations in TMEM216 as a cause ofJSRD and MKS therefore further emphasizes the interrelationship betweencell polarity, cellular morphogenesis and signal transduction pathways.

TMEM216 Nucleic Acids

In alternative embodiments, the invention provides isolated, syntheticor recombinant nucleic acids comprising a nucleotide sequence of aTMEM216 nucleic acid variant, as described herein. In alternativeembodiments, nucleotide sequences of the invention comprise at leastabout 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27,28, 29, 30, 31, 32, 33, 34, or 35 or more contiguous nucleotidesspanning the locus in one of the mutant TMEM216 genomic DNAs having oneof the nucleotide variations encoding TMEM216 protein, including R73L,R73H and R73C mutations, or the locus in one of the mutant TMEM216mRNAs, or cDNAs prepared therefrom, expressed from the mutant TMEM216genomic DNAs expressing one of the TMEM216 protein mutations, includingR73L, R73H and R73C mutations. In alternative embodiments, nucleic acidmolecules of the invention can be in a form of recombinant, synthetic,DNA, RNA, and/or a chimeric or hybrid thereof, and can be in anyphysical structure or form, e.g., including a single-strand ordouble-strand or in the form of a triple helix.

In one embodiment, isolated, synthetic or recombinant nucleic acids ofthe invention have a sequence of SEQ ID NO:2, and (complete) complementsthereof. In alternative embodiments, nucleotide sequences of theinvention comprise TMEM216 nucleic acid variants that are mutant TMEM216genomic DNAs (or equivalents) expressing one of the TMEM216 proteinvariants including R73L, R73H and R73C mutations, or those mutantTMEM216 mRNAs derived from the mutant TMEM216 genomic DNAs, expressingone of the TMEM216 protein variants including R73L, R73H and R73Cmutations, or cDNAs derived from such mRNAs. In alternative embodiments,nucleotide sequences of the invention comprise TMEM216 genomic DNAs,cDNAs and/or mRNAs (e.g., as isolated, synthetic or recombinant forms)having a full-length sequence (i.e., including the entire coding regionsand, in the case of genomic DNAs, optionally introns, promoter, andother regulatory sequences) or partial sequence (i.e., a portion of thefull-length sequence).

In one embodiment, isolated, synthetic or recombinant nucleic acids ofthe invention comprise a TMEM216 nucleic acid as an oligonucleotide,primer or probe comprising a contiguous span of the nucleotide sequenceof a mutant TMEM216 sequence (either genomic DNA or cDNA or mRNAsequence), as described herein, and spanning a cDNA locus resulting inthe expression of one of the TMEM216 protein variants, including theR73L, R73H and R73C mutations.

In alternative embodiments, an oligonucleotide, primer or probe contains(comprises or consists of) at least about 12, 13, 14, 15, 16, 17, 18,19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36,37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54,55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, to about80, 90, or 100 or more nucleotides, and alternatively from about 30 toabout 50 or more nucleotides. Exemplary TMEM216 nucleic acid sequencesof the invention are found in Supplemental Table 1 below.

In one embodiment, the oligonucleotides, primers and probes are specificto a TMEM216 nucleic acid variant of the invention. In alternativeembodiments, nucleic acids of the invention comprise sequence variationsas described in Table 1 above.

In alternative embodiments, they selectively hybridize, under stringentconditions generally recognized in the art, to a TMEM216 nucleic acidvariant of the invention, but do not substantially hybridize to areference TMEM216 nucleic acid sequence under stringent conditions. Sucholigonucleotides will be useful in hybridization-based methods, oralternatively amplification-based methods, for detecting the nucleotidevariants of the invention as described in detail below. A skilledartisan would recognize various sufficiently stringent conditions thatenable the oligonucleotides of the invention to differentiate between areference TMEM216 gene sequence and an isolated TMEM216 nucleic acidvariant of the invention. For example, in one embodiment, sufficientlystringent condition comprises the hybridization conditions comprising:hybridization overnight in a solution containing (comprising) about 50%formamide, 5×SSC, pH 7.6, 5×Denhardt's solution, 10%⁰ dextran sulfate,and 20 microgramiml denatured, sheared salmon sperm DNA. Thehybridization filters can be washed in 0.1×SSC at about 65° C.

The oligonucleotide primers or probes of the invention can have adetectable marker selected from, e.g., radioisotopes, fluorescentcompounds, enzymes, or enzyme co-factors operably linked to theoligonucleotide. The primers, probes and oligonucleotide sequences ofthe invention are useful in genotyping and haplotyping as will beapparent from the description below.

In another embodiment, TMEM216 nucleic acids are provided having 100,200, 300, 400 or 500 nucleotides or basepairs, which contain the TMEM216variant nucleotide or basepair sequences provided by SEQ ID NO: 3wherein the variations are provided above in Table 1, and/or thecomplements thereof. Such nucleic acids can be DNA or RNA, andsingle-stranded or double-stranded.

In alternative embodiments, any nucleic acid molecules containing orcomprising a sequence according to SEQ ID NO:3 and having at least oneof the variations provided in Table 1 above fall within the scope ofthis invention. For example, a hybrid nucleic acid molecule of theinvention can have a sequence according to SEQ ID NO:3 and having atleast one of the variations provided in Table 1, above operably linkedto a non-TMEM216 sequence such that the hybrid nucleic acid encodes ahybrid protein having a mutant TMEM216 peptide sequence.

In alternative embodiments, the invention provides plasmids, vectors,expression constructs and the like containing (having contained therein)one of the nucleic acid molecules of the invention. In alternativeembodiments, the plasmids, vectors, expression constructs and the likeare employed to express or amplify a nucleic acid molecule of theinvention that is contained in the vector construct. In alternativeembodiments, the plasmids, vectors, expression constructs and the likeare used in expressing a polypeptide encoded by a nucleic acid moleculeof the invention that is contained in the vector construct. Inalternative embodiments, plasmids, vectors, expression constructs andthe like include or comprise a promoter operably linked to an isolatednucleic acid molecule (e.g., a full-length sequence or 32/85 a fragmentthereof in the 5′ to 3′ direction or in the reverse direction for thepurpose of producing antisense nucleic acids), an origin of DNAreplication for the replication of the plasmids, vectors etc. in hostcells and a replication origin for the amplification of the vectors in,e.g., E. coli, and selection marker(s) for selecting and maintainingonly those host cells harboring the vectors.

In alternative embodiments, plasmids, vectors, expression constructs andthe like comprise inducible elements which function to control theexpression of the isolated gene sequence. In alternative embodiments,plasmids, vectors, expression constructs and the like comprise otherregulatory sequences such as transcriptional termination sequences andtranslation regulation sequences (e.g., Shine-Dalgarno sequence). Anepitope tag coding sequence for detection and/or purification of theencoded polypeptide can also be incorporated into the vector construct.Exemplary epitope tags include, but are not limited to, influenza virushemagglutinin (HA), Simian Virus 5 (V5), polyhistidine (6×His), c-myc,lacZ, GST, and the like. In alternative embodiments, proteins of theinvention can comprise epitope tags or polyhistidine tags, which can beeasily detected and/or purified with Ni affinity columns, while specificantibodies to many epitope tags are generally commercially available.

In alternative embodiments, plasmids, vectors, expression constructs andthe like are introduced into the host cells or organisms by anytechniques known in the art, e.g., by direct DNA transformation,microinjection, electroporation, viral infection, lipofection,biolystics (gene gun), and the like. The plasmids, vectors, expressionconstructs and the like can be maintained in host cells in anextrachromosomal state, i.e., as self-replicating plasmids or viruses.Alternatively, plasmids, vectors, expression constructs and the like canbe integrated into chromosomes of the host cells by conventionaltechniques such as selection of stable cell lines or site-specificrecombination. Plasmids, vectors, expression constructs and the like canbe designed to be suitable for expression in various host cells,including but not limited to bacteria, yeast cells, plant cells, insectcells, and mammalian and human cells. A skilled artisan will recognizethat the designs of the plasmids, vectors, expression constructs and thelike can vary with the host used.

In alternative embodiments, a nucleic acid of the invention, e.g., aTMEM216 nucleic acid, is incorporated in an array, a microchip ormicroarray, or other similar (equivalent) structures. In alternativeembodiments the microarray allows rapid genotyping and/or haplotyping ina large scale. In alternative embodiments, in the arrays or microchips,a large number of different nucleic acids are attached or immobilized inan array on a solid support, e.g., a silicon chip or glass slide. Targetnucleic acid sequences to be analyzed can be contacted with theimmobilized nucleic acids on the microchip. See Lipshutz et al.,Biotechniques, 19:442-447 (1995); Chee et al., Science, 274:610-614(1996); Kozal et al., Nat. Med. 2:753-759 (1996); Hacia et al., Nat.Genet., 14:441-447 (1996); Saiki et al., Proc. Natl. Acad. Sci. USA,86:6230-6234 (1989), Gingeras et al., Genome Res., 8:435-448 (1998). Themicrochip technologies combined with computerized analysis tools allowlarge-scale high throughput screening. See, e.g., U.S. Pat. No.5,925,525 to Fodor et al; Wilgenbus et al., J. Mol. Med., 77:761-786(1999); Graber et al., Curr. Opin. Biotechnol., 9:14-18 (1998); Hacia etal., Nat. Genet., 14:441-447 (1996); Shoemaker et al., Nat. Genet.,14:450-456 (1996); DeRisi et al., Nat. Genet., 14:457-460 (1996); Cheeet al., Nat. Genet., 14:610-614 (1996). Lockhart et al., Nat. Genet.,14:675-680 (1996); Drobyshev et al., Gene, 188:45-52 (1997).

In alternative embodiments, a microarray is provided comprising one or aplurality of the nucleic acids of the invention such that one, severalor all of the nucleotide identities at each of the genetic variant sitesdisclosed in Table 1 can be determined in one single microarray.

TMEM216 Polypeptides

In alternative embodiments, the invention provides isolated, syntheticor recombinant polypeptides having an amino acid sequence of a TMEM216protein variant, as described herein. In alternative embodiments theamino acid sequence is a contiguous sequence of at least about 3, 4, 5,6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24,25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42,43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60,61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78,79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96,97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111,112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125,126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139,140, 141, 142, 143, 144, 145, 146, 147, or 148 amino acids of SEQ IDNO:1 comprising one or more of the variations provided in Table 1 above.In alternative embodiments, the amino acid sequence can also be acontiguous sequence of at least 3, 4, 5. 6, 7, 8, 9, 10, 12, 13, 14, 15,16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, or 30 or moreamino acids of SEQ ID NO:6 comprising one or more of the variationsprovided in Table 1 above. In alternative embodiments, the amino acidsequence can also be a contiguous sequence of at least 3, 4, 5, 6, 7, 8,9, 10, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27,28, 29, 30, 31, 32, or 33 or more amino acids of SEQ ID NO:9 comprisingone or more of the variations provided in Table 1 above. In alternativeembodiments, the amino acid sequence can also be a contiguous sequenceof at least 3, 4, 5, 6, 7, 8, 9, 10, 12, 13, 14, 15, 16, 17, 18, 19, 20,21, 22, 23, 24, or 25 or more amino acids of SEQ ID NO: 12 comprisingone or more of the variations provided in Table 1 above.

In alternative embodiments, the invention provides isolated TMEM216protein variants, as described herein, that can be initially isolatedfrom a patient having a variation provided in Table 1 above. Inalternative embodiments, TMEM216 protein variants of the invention alsoinclude other amino acid variants, such as those created as a result ofsingle nucleotide polymorphisms in the coding sequence of the TMEM216gene.

In alternative embodiments, hybrid proteins of the invention can haveone or more or all of the above-described mutant TMEM216 amino acidsequences and a non-TMEM216 amino acid sequence.

In alternative embodiments, nucleic acids and polypeptides of theinvention can be prepared using techniques generally known in the fieldof protein biochemistry and molecular biology. See e.g., Sambrook etal., Molecular Cloning: A Laboratory Manual, 2nd ed., Cold Spring HarborLaboratory, Cold Spring Harbor, N.Y., 1989.

Antibodies

In alternative embodiments, the invention also provides antibodiesselectively immunoreactive with a protein or peptide of the invention,e.g., a TMEM216 protein variant.

In alternative embodiments, the term “antibody” encompasses bothmonoclonal and polyclonal antibodies that fall within any antibodyclasses, e.g., IgG. IgM, IgA, etc. The term “antibody” also includesantibody fragments including, but not limited to, Fab and F(ab′)₂,conjugates of such fragments, and single-chain antibodies that can bemade in accordance with U.S. Pat. No. 4,704,692, which is incorporatedherein by reference.

In alternative embodiments the phrase “selectively immunoreactive withan isolated TMEM216 protein variant of the invention” means that theimmunoreactivity of the antibody of the invention with a TMEM216 proteinvariant of the invention is substantially or distinguishably higher thanthat with a TMEM216 protein heretofore known in the art (e.g., a wildtype TMEM216 protein). For example, in one embodiment, the binding of anantibody of the invention to a protein of the invention is readilydistinguishable from the binding of the antibody to a TMEM216 proteinknown in the art (e.g., a wild type TMEM216 protein), based on e.g., thestrength of the binding affinities. In alternative embodiments, thebinding constant differs by a magnitude of at least 2 fold, or at least5 fold, or at least 10 fold, or at least 100 fold.

In alternative embodiments, to make the antibody, a TMEM216 proteinvariant of the invention, or a suitable fragment thereof, can be used toimmunize an animal. The TMEM216 protein variant can be made by anymethods known in the art, e.g., by recombinant expression or chemicalsynthesis. In alternative embodiments, a mutant TMEM216 protein fragmenthaving an amino acid sequence selected from SEQ ID NOs: 1, 6, 9 or 12,wherein the sequence comprises a variation provided in Table 1 above,can also be used. In alternative embodiments, the mutant TMEM216 proteinfragment consists of less than 100 amino acids, or less than 50 aminoacids, or less than 25 amino acids. As a result, a greater portion ofthe total antibodies are selectively immunoreactive with a TMEM216protein variant of the invention. Techniques for immunizing animals forthe purpose of making polyclonal antibodies are generally known in theart. See Harlow and Lane, Antibodies: A Laboratory Manual, Cold SpringHarbor Laboratory, Cold Spring Harbor, N.Y., 1988. A carrier may benecessary to increase the immunogenicity of the polypeptide. Suitablecarriers known in the art include, but are not limited to, liposome,macromolecular protein or polysaccharide, or combination thereof.Preferably, the carrier has a molecular weight in the range of about10,000 to 1,000,000. The polypeptide may also be administered along withan adjuvant, e.g., complete Freund's adjuvant.

In alternative embodiments, antibodies of the invention are synthetic ormonoclonal. Such monoclonal antibodies may be developed using anyconventional techniques known in the art. For example, the popularhybridoma method disclosed in Kohler and Milstein, Nature, 256:495-497(1975); see e.g., U.S. Pat. No. 4,376,110. In alternative embodiments,B-lymphocytes producing a polyclonal antibody against a protein variantof the invention can be fused with myeloma cells to generate a libraryof hybridoma clones. The hybridoma population is then screened forantigen binding specificity and also for immunoglobulin class (isotype).In this manner, pure hybridoma clones producing specific homogenousantibodies can be selected. See e.g., Harlow and Lane. Antibodies: ALaboratory Manual, Cold Spring Harbor Press, 1988. Alternatively, othertechniques known in the art may also be used to prepare monoclonalantibodies, which include but are not limited to the EBV hybridomatechnique, the human N-cell hybridoma technique, and the triomatechnique.

In alternative embodiments, antibodies of the invention, e.g., thoseselectively immunoreactive with a protein of the invention, may also berecombinantly or synthetically produced. In alternative embodiments,cDNAs prepared by PCR amplification from activated B-lymphocytes orhybridomas may be cloned into an expression vector to form a cDNAlibrary, which is then introduced into a host cell for recombinantexpression. The cDNA encoding a specific desired protein may then beisolated from the library. The isolated cDNA can be introduced into asuitable host cell for the expression of the protein. In alternativeembodiments recombinant techniques are used to recombinantly producespecific native antibodies, hybrid antibodies capable of simultaneousreaction with more than one antigen, chimeric antibodies (e.g., theconstant and variable regions are derived from different sources),univalent antibodies which comprise one heavy and light chain paircoupled with the Fc region of a third (heavy) chain, Fab proteins, andthe like. See U.S. Pat. No. 4,816,567; European Patent Publication No.0088994; Munro, Nature, 312:597 (1984); Morrison, Science, 229:1202(1985); Oi et al., BioTechniques, 4:214 (1986); and Wood et al., Nature,314:446-449 (1985), all of which are incorporated herein by reference.Antibody fragments such as Fv fragments, single-chain Fv fragments(scFv). Fab′ fragments, and F(ab′).sub.2 fragments can also berecombinantly produced by methods disclosed in, e.g., U.S. Pat. No.4,946,778; Skerra & Pluckthun, Science, 240:1038-1041 (1988); Better etal., Science, 240:1041-1043 (1988); and Bird, et al., Science,242:423-426 (1988).

In alternative embodiments, antibodies of the invention are partially orfully humanized antibodies. For this purpose, any methods known in theart may be used. For example, partially humanized chimeric antibodieshaving V regions derived from the tumor-specific mouse monoclonalantibody, but human C regions are disclosed in Morrison and Oi, Adv.Immunol., 44:65-92 (1989). In alternative embodiments, fully humanizedantibodies can be made using transgenic non-human animals. For example,transgenic non-human animals such as transgenic mice can be produced inwhich endogenous immunoglobulin genes are suppressed or deleted, whileheterologous antibodies are encoded entirely by exogenous immunoglobulingenes, preferably human immunoglobulin genes, recombinantly introducedinto the genome. See e.g., U.S. Pat. Nos. 5,530,101; 5,545,806;6,075,181; PCT Publication No. WO 94/02602; Green et. al., Nat.Genetics, 7: 13-21 (1994); and Lonberg et al., Nature 368: 856-859(1994), all of which are incorporated herein by reference. Thetransgenic non-human host animal may be immunized with suitable antigenssuch as a protein of the invention to illicit specific immune responsethus producing humanized antibodies.

In alternative embodiments, cell lines producing specific humanizedantibodies are derived from the immunized transgenic non-human animals.For example, mature B-lymphocytes obtained from a transgenic animalproducing humanized antibodies can be fused to myeloma cells and theresulting hybridoma clones may be selected for specific humanizedantibodies with desired binding specificities. In alternativeembodiments, cDNAs may be extracted from mature B-lymphocytes and usedin establishing a library that is subsequently screened for clonesencoding humanized antibodies with desired binding specificities. Inaddition, antibodies may also be produced in transgenic plantscontaining recombinant nucleic acids encoding antibodies.

In alternative embodiments, the invention provides arrays, microarrays,protein microchips or macroarrays having (1) a protein or antibody ofthe invention, e.g., a TMEM216 protein variant of the invention or afragment thereof, e.g., comprising an amino acid sequence according toSEQ ID NO: 1, SEQ ID NO:6, SEQ ID NO:9 or SEQ ID NO: 12, and/or having avariation as provided herein, e.g., in Table 1 above, and anycombination of these protein variants; and/or (2) an antibodyselectively immunoreactive with a protein of the invention, e.g., aTMEM216 protein variant of the invention.

In alternative embodiments, the invention provides arrays, microarrays,protein microchips or macroarrays for proteomics research and/orprotein-based detection and diagnosis of diseases. In alternativeembodiments the arrays, microarrays, protein microchips or macroarraysof the invention (e.g., protein microarrays of the invention) are usefulin a variety of applications including, e.g., high throughput screeningfor compounds capable of modulating the activities of a polypeptide ofthe invention, e.g., a TMEM216 protein variant of the invention. Inalternative embodiments, protein or nucleic acid arrays, microarrays,microchips or macroarrays are also useful in detecting a polypeptide ornucleic acid of the invention, e.g., a mutant TMEM216 protein of theinvention, and thus can be used in determining a predisposition to, orthe presence of, e.g., Joubert Syndrome and Related Disorders (JSRD) andMeckel Syndrome (MKS) in patients, particularly in the Ashkenazi Jewishpopulation.

In alternative embodiments, the arrays, microarrays, microchips ormacroarrays of the invention are prepared by a number of methods knownin the art. An exemplary method is disclosed in e.g., MacBeath andSchreiber, Science, 289:1760-1763 (2000). For example, glass microscopeslides are treated with an aldehyde-containing silane reagent(SuperAldehyde Substrates purchased from TeleChem International,Cupertino, Calif.). Nanoliter volumes of protein samples in aphosphate-buffered saline with 40% glycerol are then spotted onto thetreated slides using a high-precision contact-printing robot. Afterincubation, the slides are immersed in a bovine serum albumin(BSA)-containing buffer to quench the unreacted aldehydes and to form aBSA layer which functions to prevent non-specific protein binding insubsequent applications of the microchip. Alternatively, as disclosed inMacBeath and Schreiber, proteins or protein complexes of the inventioncan be attached to a BSA-NHS slide by covalent linkages. BSA-NHS slidesare fabricated by first attaching a molecular layer of BSA to thesurface of glass slides and then activating the BSA withN,N′-disuccinimidyl carbonate. As a result, the amino groups of thelysine, aspartate, and glutamate residues on the BSA are activated andcan form covalent urea or amide linkages with protein samples spotted onthe slides. See MacBeath and Schreiber, Science, 289:1760-1763 (2000).

Another example of useful method for preparing an array, chip,microchip, e.g., a protein microchip, of the invention is disclosed inPCT Publication Nos. WO 00/4389A2 and WO 00/04382. For example, asubstrate or chip base is covered with one or more layers of thinorganic film to eliminate any surface defects, insulate proteins fromthe base materials, and to ensure a uniform protein array. Next, aplurality of protein-capturing agents (e.g., antibodies, peptides, etc.)are arrayed and attached to the base that is covered with the thin film.Proteins or protein complexes can then be bound to the capturing agentsforming a protein microarray. The protein microchips are kept in flowchambers with an aqueous solution.

Another example of useful method for preparing an array, chip,microchip, e.g., a protein microchip, of the invention is disclosed inPCT Publication No. WO 99/36576. For example, a three-dimensionalhydrophilic polymer matrix, i.e., a gel, is first deposited on a solidsubstrate such as a glass slide. The polymer matrix gel is capable ofexpanding or contracting and contains a coupling reagent that reactswith amine groups. Thus, proteins and protein complexes can be contactedwith the matrix gel in an expanded aqueous and porous state to allowreactions between the amine groups on the protein or protein complexeswith the coupling reagents thus immobilizing the proteins and proteincomplexes on the substrate. Thereafter, the gel is contracted to embedthe attached proteins and protein complexes in the matrix gel.

Alternatively, nucleic acids, proteins and protein complexes of theinvention can be incorporated into a commercially available proteinmicrochip, e.g., the PROTEINCHIP™ (ProteinChip) system from CiphergenBiosystems Inc., Palo Alto, Calif. The ProteinChip System comprisesmetal chips having a treated surface that interact with proteins. Forexample, a metal chip surface is coated with a silicon dioxide film. Themolecules of interest such as proteins and protein complexes can then beattached covalently to the chip surface via a silane coupling agent.

An array, chip, microchip, e.g., a protein or nucleic acid microchip, ofthe invention can also be prepared with other methods known in the art,e.g., those disclosed in U.S. Pat. Nos. 6,087,102, 6,139,831, 6,087,103;PCT Publication Nos. WO 99/60156, WO 99/39210, WO 00/54046, WO 00/53625,WO 99/51773, WO 99/35289, WO 97/42507, WO 01/01142, WO 00/63694, WO00/61806, WO 99/61148, WO 99/40434.

Genotyping and Genetic Prognosis and Diagnosis

In alternative embodiments, the invention provides compositions and,methods for determining or predicting a predisposition to, or thepresence of, a ciliopathy (or any genetic disorder of a cellular ciliaor cilia anchoring structure, basal body or ciliary function) in anindividual, e.g., determining or predicting a predisposition to, or thepresence of a Joubert Syndrome and Related Disorders (JSRD) and/or aMeckel Syndrome (MKS), e.g., in the Ashkenazi Jewish population.

In alternative embodiments the TMEM216 gene variations of (e.g.,identified by) the invention are deleterious and predispose individualshaving those sequences to e.g., a ciliopathy. Thus, in practicing acomposition or method of the invention, the presence or absence of oneor more of the TMEM216 variants of the invention can be detected in anindividual. In one embodiment, using this information, one of skill canreasonably predict a predisposition to, or the presence of, one of thoseciliopathies, e.g., e.g., a Joubert Syndrome and Related Disorders(JSRD) and/or Meckel Syndrome (MKS), particularly in the AshkenaziJewish population.

In alternative embodiments, any technique for detecting a geneticvariant known in the art is used to practice a method or composition ofthis invention. The techniques can be nucleic acid-based orprotein-based. In alternative embodiments, the techniques used aresufficiently sensitive so as to accurately detect the nucleotide oramino acid variations. In alternative embodiments, a probe is utilizedwhich is labeled with a detectable marker. In alternative embodiments,any suitable marker known in the art can be used, including but notlimited to, radioactive isotopes, fluorescent compounds, biotin which isdetectable using streptavidin, enzymes (e.g., alkaline phosphatase),substrates of an enzyme, ligands and antibodies, etc. See Jablonski etal., Nucleic Acids Res., 14:6115-6128 (1986); Nguyen et al.,Biotechniques, 13:116-123 (1992); Rigby et al., J. Mol. Biol.,113:237-251 (1977).

In alternative embodiments, a DNA-based detection method, a target DNAsample is used. For example, a sample containing a TMEM216 gene sequenceshould be obtained from the individual to be tested. Any tissue or cellsample containing the TMEM216 genomic DNA or mRNA, or a portion thereof,can be used. In alternative embodiments, a tissue sample containing cellnuclei and thus genomic DNA can be obtained from the individual. Bloodsamples can also be useful, except that only white blood cells and otherlymphocytes have cell nuclei, while red blood cells are enucleated andcontain mRNA. In alternative embodiments, mRNA is used, as it can beanalyzed for the presence of nucleotide variants in its sequence orserve as template for cDNA synthesis. The tissue or cell samples can beanalyzed directly without much processing. Alternatively, nucleic acidsincluding the target TMEM216 nucleic acids can be extracted, purified,or amplified before they are subject to the various detecting proceduresdiscussed below. Other than tissue or cell samples, cDNAs or genomicDNAs from a cDNA or genomic DNA library constructed using a tissue orcell sample obtained from the individual to be tested are also useful.

In alternative embodiments, to determine the presence or absence of asequence of the invention, e.g., a mutation identified herein, atechnique comprising sequencing a target TMEM216 genomic DNA or cDNA isused, e.g., where a the region spanning the genetic variation isdetected and sequenced. In alternative embodiments any sequencingtechnique known in the art is used, e.g., the Sanger method and theGilbert chemical method, or a pyrosequencing method (to monitor DNAsynthesis in real time using a luminometric detection system).Pyrosequencing can be effective in analyzing genetic polymorphisms suchas single-nucleotide polymorphisms; see e.g., Nordstrom et al.,Biotechnol. Appl. Biochem., 31(2): 107-112 (2000); Ahmadian et al.,Anal. Biochem., 280:103-110 (2000). For example, sequencing primers canbe designed based on either mutant or wild-type TMEM216 gene intronic orexonic sequences such that the primers have the nucleotide sequenceadjacent to a variation identified herein. In another example, PCRprimers are designed based on either mutant or wild-type TMEM216 geneintronic or exonic sequences such that PCR amplification generates aTMEM216 DNA fragment spanning the deletion locus. Such primers can bethose provided in Supplemental Table 1 below.

In alternative embodiments, restriction fragment length polymorphism(RFLP) methods are used; e.g., for the elimination and creation ofrestriction enzyme recognition sites. Digestion of the mutant TMEM216genomic DNAs or cDNAs with appropriate restriction enzyme(s) cangenerate restriction fragment length patterns distinct from thosegenerated from wild-type TMEM216 genomic DNA or cDNA. In alternativeembodiments, variations in TMEM216 of the invention can be detected byRFLP. In alternative embodiments RFLP techniques known in the art to theinvention are used.

In alternative embodiments, genomic DNA can be obtained from a patientsample and digested by appropriate restriction enzyme(s). Southern blotcan be performed using a probe having a wild-type TMEM216 sequence thatis missing from one or more of the TMEM216 genetic variants of theinvention. Alternatively, probes specific to the mutant TMEM216 nucleicacids of the invention can also be used.

In alternative embodiments, the presence or absence of a sequence of theinvention, e.g., a TMEM216 mutation of the invention, is detected usingthe amplification refractory mutation system (ARMS) technique. See e.g.,European Patent No. 0,332,435; Newton et al., Nucleic Acids Res.,17:2503-2515 (1989); Fox et al., Br. J. Cancer, 77:1267-1274 (1998);Robertson et al., Eur. Respir. J., 12:477-482 (1998). In the ARMSmethod, a primer is synthesized matching the nucleotide sequenceimmediately 5′ upstream from the locus being tested except that the3′-end nucleotide which corresponds to the nucleotide at the locus is apredetermined nucleotide. For example, the 3′-end nucleotide can be thesame as that in the mutated locus. The primer can be of any suitablelength so long as it hybridizes to the target DNA under stringentconditions only when its 3′-end nucleotide matches the nucleotide at thelocus being tested. Preferably the primer has at least 12 nucleotides,more preferably from about 18 to 50 nucleotides. If the individualtested has a mutation at the locus and the nucleotide therein matchesthe 3′-end nucleotide of the primer, then the primer can be furtherextended upon hybridizing to the target DNA template, and the primer caninitiate a PCR amplification reaction in conjunction with anothersuitable PCR primer. In contrast, if the nucleotide at the locus is ofwild type, then primer extension cannot be achieved. Various forms ofARMS techniques developed in the past few years can be used. See e.g.,Gibson et al., Clin. Chem. 43:1336-1341 (1997). Thus, for example,primers having a sequence selected from SEQ ID NOs:42-47, 53-63, and70-79 can all be useful in this technique.

In alternative embodiments, the mini sequencing or single nucleotideprimer extension method (similar to the ARMS technique, which is basedon the incorporation of a single nucleotide) is used. In alternativeembodiments, an oligonucleotide primer matching the nucleotide sequenceimmediately 5′ to the locus being tested is hybridized to the target DNAor mRNA in the presence of labeled dideoxyribonucleotides. A labelednucleotide is incorporated or linked to the primer only when thedideoxyribonucleotides matches the nucleotide at the variant locus beingdetected. Thus, the identity of the nucleotide at the variant locus canbe revealed based on the detection label attached to the incorporateddideoxyribonucleotides. See Syvanen et al., Genomics, 8:684-692 (1990);Shumaker et al., Hum. Mutat., 7:346-354 (1996); Chen et al., GenomeRes., 10:549-547 (2000).

In alternative embodiments other techniques useful in the inventioninclude “oligonucleotide ligation assays” (OLA), in whichdifferentiation between a wild-type locus and a mutation is based on theability of two oligonucleotides to anneal adjacent to each other on thetarget DNA molecule allowing the two oligonucleotides joined together bya DNA ligase. See Landergren et al., Science, 241:1077-1080 (1988); Chenet al, Genome Res., 8:549-556 (1998); Iannone et al., Cytometry,39:131-140 (2000). Thus, for example, to detect a mutation at aparticular locus in the TMEM216 gene, two oligonucleotides can besynthesized, one having the TMEM216 sequence just 5′ upstream from thelocus with its 3′ end nucleotide being identical to the nucleotide inthe mutant locus of the TMEM216 gene, the other having a nucleotidesequence matching the TMEM216 sequence immediately 3′ downstream fromthe locus in the TMEM216 gene. The oligonucleotides can be labeled forthe purpose of detection. Upon hybridizing to the target TMEM216 geneunder a stringent conditions, the two oligonucleotides are subjected toligation in the presence of a suitable ligase. The ligation of the twooligonucleotides would indicate that the target DNA has a nucleotidevariant at the locus being detected. Thus, for example, oligonucleotidescan be readily designed based on the loci present in mutant TMEM216genomic DNA or cDNA sequences that are provided in Table 1 above.

In alternative embodiments screening for or detection of a genetic orsequence variation is accomplished by a variety of hybridization-basedapproaches. In alternative embodiments Allele-specific oligonucleotidesare used, see e.g., Conner et al., Proc. Natl. Acad. Sci. USA,80:278-282 (1983); Saiki et al, Proc. Natl. Acad. Sci. USA, 86:6230-6234(1989). Oligonucleotide probes hybridizing specifically to a TMEM216gene allele having a particular gene variant at a particular locus butnot to other alleles can be designed by methods known in the art. Theprobes can have a length of, e.g., from about 10 to about 50 nucleotidebases. The target TMEM216 genomic DNA or cDNA and the oligonucleotideprobe can be contacted with each other under conditions sufficientlystringent such that the genetic variant can be distinguished from thewild-type TMEM216 gene based on the presence or absence ofhybridization. Examples of such probes and primers are provided inSupplemental Table 1 below. The probe can be labeled to providedetection signals. Alternatively, the allele-specific oligonucleotideprobe can be used as a PCR amplification primer in an “allele-specificPCR” and the presence or absence of a PCR product of the expected lengthwould indicate the presence or absence of a particular genetic variant.In alternative embodiments, oligos having a sequence selected from thoseprovided in Supplemental Table 1 below can be used.

In alternative embodiments, mass spectrometry is used, e.g., see Graberet al., Curr. Opin. Biotechnol., 9:14-18 (1998). For example, in theprimer oligo base extension (PROBE™) method, a target nucleic acid isimmobilized to a solid-phase support. A primer is annealed to the targetimmediately 5′ upstream from the locus to be analyzed. Primer extensionis carried out in the presence of a selected mixture ofdeoxyribonucleotides and dideoxyribonucleotides. The resulting mixtureof newly extended primers is then analyzed by MALDI-TOF. See e.g.,Monforte et al., Nat. Med., 3:360-362 (1997). In another example,primers can be designed based on either mutant or wild-type TMEM216 geneintronic or exonic sequences such that the primers have the nucleotidesequences adjacent to and flanking a locus identified in accordance withthe invention. PCR amplification on a patient sample is carried outusing the primers. Mass spectrometry is then performed on the PCRproduct.

In alternative embodiments, a microchip or microarray technologies isused to practice a detection method of the invention. For example, inmicrochips, a large number of different oligonucleotide probes areimmobilized in an array on a substrate or carrier, e.g., a silicon chipor glass slide. Target nucleic acid sequences to be analyzed can becontacted with the immobilized oligonucleotide probes on the microchip.See Lipshutz et al., Biotechniques, 19:442-447 (1995); Chee et al.,Science, 274:610-614 (1996); Kozal et al., Nat. Med. 2:753-759 (1996);Hacia et al., Nat. Genet., 14:441-447 (1996); Saiki et al., Proc. Natl.Acad. Sci. USA, 86:6230-6234 (1989); Gingeras et al., Genome Res.,8:435-448 (1998). Alternatively, the multiple target nucleic acidsequences to be studied are fixed onto a substrate and an array ofprobes is contacted with the immobilized target sequences. See Drmanacet al., Nat. Biotechnol., 16:54-58 (1998). Numerous microchiptechnologies have been developed incorporating one or more of the abovedescribed techniques for detecting mutations particularly SNPs. Themicrochip technologies combined with computerized analysis tools allowfast screening in a large scale. In alternative embodiments, adaptationsof microchip technologies are used, see, e.g., U.S. Pat. No. 5,925,525to Fodor et al; Wilgenbus et al., J. Mol. Med., 77:761-786 (1999);Graber et al., Curr. Opin. Biotechnol., 9:14-18 (1998); Hacia et al.,Nat. Genet., 14:441-447 (1996); Shoemaker et al., Nat. Genet.,14:450-456 (1996); DeRisi et al., Nat. Genet., 14:457-460 (1996); Cheeet al., Nat. Genet., 14:610-614 (1996); Lockhart et al., Nat. Genet.,14:675-680 (1996); Drobyshev et al., Gene, 188:45-52 (1997).

In alternative embodiments, it may or may not be necessary to amplify atarget nucleic acid, e.g., an RNA or a DNA, e.g., a TMEM216 genomic DNAor cDNA sequence to e.g., increase the number of target DNA molecules,depending on the detection techniques used. For example, most PCR-basedtechniques combine the amplification of a portion of the target and thedetection of mutations. In alternative embodiments, any PCRamplification technique known in the art is used, e.g., as disclosed inU.S. Pat. Nos. 4,683,195 and 4,800,159. For non-PCR-based detectiontechniques, if necessary, the amplification can be achieved by, e.g., invivo plasmid multiplication, or by purifying the target DNA from a largeamount of tissue or cell samples. See generally, Sambrook et al.,Molecular Cloning: A Laboratory Manual, 2nd ed., Cold Spring HarborLaboratory, Cold Spring Harbor, N.Y., 1989. However, even with scarcesamples, many sensitive techniques have been developed in which geneticvariations can be detected without having to amplify the target DNA inthe sample. For example, techniques have been developed that amplify thesignal as opposed to the target DNA by, e.g., employing branched DNA ordendrimers that can hybridize to the target DNA. The branched ordendrimer DNAs provide multiple hybridization sites for hybridizationprobes to attach thereto thus amplifying the detection signals. SeeDetmer et al., J. Clin. Microbiol., 34:901-907 (1996); Collins et al.,Nucleic Acids Res., 25:2979-2984 (1997); Horn et al., Nucleic AcidsRes., 25:4835-4841 (1997); Horn et al., Nucleic Acids Res., 25:4842-4849(1997); Nilsen et al., J. Theor. Biol., 187:273-284 (1997).

In alternative embodiments, techniques that avoid amplification areused, e.g., surface-enhanced resonance Raman scattering (SERRS),fluorescence correlation spectroscopy, and single-moleculeelectrophoresis. In SERRS, a chromophore-nucleic acid conjugate isabsorbed onto colloidal silver and is irradiated with laser light at aresonant frequency of the chromophore. See Graham et al., Anal. Chem.,69:4703-4707 (1997). The fluorescence correlation spectroscopy is basedon the spatio-temporal correlations between fluctuating light signalsand trapping single molecules in an electric field. See Eigen et al.,Proc. Natl. Acad. Sci. USA. 91:5740-5747 (1994). In single-moleculeelectrophoresis, the electrophoretic velocity of a fluorescently taggednucleic acid is determined by measuring the time required for themolecule to travel a predetermined distance between two laser beams. SeeCastro et al., Anal. Chem., 67:3181-3186 (1995). In alternativeembodiments, the Invader assay and the rolling circle amplificationtechnique are used: see e.g. Lyamichev et al., Nat. Biotechnol.,17:292-296 (1999); Lizardi et al., Nature Genetics, 19:225-232 (1998).

In alternative embodiments, allele-specific oligonucleotides (ASO) areused in in situ hybridization using tissues or cells as samples. Theoligonucleotide probes which can hybridize differentially with thewild-type gene sequence or the gene sequence harboring a mutation may belabeled with radioactive isotopes, fluorescence, or other detectablemarkers. In situ hybridization techniques are well known in the art andtheir adaptation to the invention for detecting the presence or absenceof a genetic variant in the TMEM216 gene of a particular individualshould be apparent to a skilled artisan apprised of this disclosure.

In alternative embodiments protein-based detection techniques are used,e.g., when a genetic variant causes an amino acid substitution ordeletion or insertions that affects the protein primary, secondary ortertiary structure. To detect the amino acid variations, proteinsequencing techniques may be used. For example, a TMEM216 protein orfragment thereof can be synthesized by recombinant expression using aTMEM216 DNA fragment isolated from an individual to be tested. Inalternative embodiments, a TMEM216 cDNA fragment of no more than 100 to150 base pairs encompassing the polymorphic locus to be determined isused. The amino acid sequence of the peptide can then be determined byconventional protein sequencing methods. Alternatively, the recentlydeveloped HPLC-microscopy tandem mass spectrometry technique can be usedfor determining the amino acid sequence variations. In this technique,proteolytic digestion is performed on a protein, and the resultingpeptide mixture is separated by reversed-phase chromatographicseparation. Tandem mass spectrometry can be performed and the datacollected therefrom is analyzed. See Gatlin et al., Anal. Chem.,72:757-763 (2000).

In alternative embodiments, other useful protein-based detectiontechniques include immunoaffinity assays based on antibodies selectivelyimmunoreactive with mutant TMEM216 proteins according to the invention.Such antibodies may react specifically with epitopes comprising thepolypeptide fragments spanning the junction regions of TMEM216 proteinsthat correspond to loci in the mutant TMEM216 mRNAs transcribed from themutant TMEM216 genomic DNAs of the invention. Alternatively, suchantibodies may react specifically with epitopes present on the novelTMEM216 protein variants provided in Table 1 above. Examples ofidentified epitopes are provided in the Examples section herein. Methodsfor producing such antibodies are described above in detail. Antibodiescan be used to immunoprecipitate specific proteins from solution samplesor to immunoblot proteins separated by, e.g., polyacrylamide gels.Immunocytochemical methods can also be used in detecting specificprotein polymorphisms in tissues or cells. In alternative embodimentsantibody-based techniques are used including, e.g., enzyme-linkedimmunosorbent assay (ELISA), radioimmunoassay (RIA), immunoradiometricassays (IRMA) and immunoenzymatic assays (IEMA), including sandwichassays using monoclonal or polyclonal antibodies. See e.g., U.S. Pat.Nos. 4,376,110 and 4,486,530, both of which are incorporated herein byreference.

In alternative embodiments the invention provide compositions andmethods for genotyping a TMEM216 gene of an individual to determine, inthe individual, the presence or absence of a TMEM216 genetic variant,e.g., as provided in Table 1 above.

In alternative embodiments, once the presence or absence of a TMEM216genetic variant of the invention is determined, the result can be castin a communicable form that can be communicated to the individualpatient or physician. Such a form can vary and can be tangible orintangible. The result with regard to the presence or absence of aTMEM216 genetic variant of the invention in the individual tested can beembodied in descriptive statements, diagrams, photographs, charts,images or any other visual forms. For example, images of gelelectrophoresis of PCR products can be used in explaining the results.In alternative embodiments diagrams showing where a variation occurs inan individual's TMEM216 gene are used in communicating the test results.The statements and visual forms can be recorded on a tangible media suchas papers, computer readable media such as floppy disks, compact disks,etc., or on an intangible media, e.g., an electronic media in the formof e-mail, or on a preferably secured website on the internet or anintranet, etc. In alternative embodiments, the result with regard to thepresence or absence of a TMEM216 genetic variant of the invention in theindividual tested is recorded in a sound form and transmitted throughany suitable media, e.g., analog or digital cable lines, fiber opticcables, etc., via telephone, facsimile, wireless mobile phone, internetphone and the like.

The invention also provides kits for practicing compositions and methodsof the invention, e.g., the genotyping methods of the invention. Thekits may include a carrier for the various components of the kit. Thecarrier can be a container or support, in the form of, e.g., bag, box,tube, rack, and is optionally compartmentalized. The carrier may definean enclosed confinement for safety purposes during shipment and storage.In alternative embodiments the kit also includes various componentsuseful in detecting nucleotide or amino acid sequence of the invention,e.g., the TMEM216 variants of the invention, using e.g., any detectiontechniques.

In one embodiment, the detection kit includes one or moreoligonucleotides useful in detecting nucleotide or amino acid sequenceof the invention, e.g., the TMEM216 variants of the invention, e.g., thegenomic variants in TMEM216 sequences of the invention. In alternativeembodiments, the oligonucleotides are designed such that they arespecific to a TMEM216 nucleic acid (variant) of the invention understringent conditions. In alternative embodiments, the oligonucleotidesare designed such that they can distinguish one genetic variant fromanother at a particular locus under predetermined stringenthybridization conditions. Examples of such oligonucleotides includenucleic acids having a sequence of the invention as described inSupplemental Table 1 below. In alternative embodiments, theoligonucleotides can be used in mutation-detecting techniques such asallele-specific oligonucleotides (ASO), allele-specific PCR. TAQMAN™(TaqMan)-based quantitative PCR, chemiluminescence-based techniques,molecular beacons, and improvements or derivatives thereof, e.g.,microchip technologies.

In another embodiment of this invention, the kit includes one or moreoligonucleotides suitable for use in detecting techniques such as ARMS,oligonucleotide ligation assay (OLA), and the like. For example, theoligonucleotides in this embodiment include a TMEM216 gene sequenceimmediately 5′ upstream from a locus to be analyzed. The 3′ endnucleotide of the oligo is the first nucleotide on the 3′ side of thelocus. Examples of suitable oligos include, but are not limited to,those consisting of a sequence selected from those provided inSupplemental Table 1 below.

In alternative embodiments, oligonucleotides in a detection kit can belabeled with any suitable detection marker including but not limited to,radioactive isotopes, fluorophores, biotin, enzymes (e.g., alkalinephosphatase), enzyme substrates, ligands and antibodies, etc. SeeJablonski et al., Nucleic Acids Res., 14:6115-6128 (1986); Nguyen etal., Biotechniques, 13:116-123 (1992); Rigby et al., J. Mol. Biol.,113:237-251 (1977). Alternatively, the oligonucleotides included in thekit are not labeled, and instead, one or more markers are provided inthe kit so that users may label the oligonucleotides at the time of use.

In another embodiment of the invention, the detection kit contains oneor more antibodies selectively immunoreactive with a protein of theinvention, e.g., a TMEM216 protein (variant) of the invention. Methodsfor producing and using such antibodies have been described above indetail. In another embodiment other components are used in the detectiontechnique and are included in a detection kit of this invention.Examples of such components include, but are not limited to, DNApolymerase, reverse transcriptase, deoxyribonucleotides,dideoxyribonucleotides other primers suitable for the amplification of atarget DNA or mRNA sequence, RNase A, mutS protein, and the like. Inaddition, the detection kit preferably includes instructions on usingthe kit for detecting genetic variants in TMEM216 gene sequences,particularly the genetic variants of the invention.

Screening Assays

The invention provides compositions and methods for identifyingcompounds capable of modulating, e.g., enhancing or inhibiting, theactivities of a protein of the invention, e.g., a TMEM216 protein(variant) of the invention. In alternative embodiments, these identifiedcompounds are useful in treating or preventing symptoms associated withdecreased TMEM216 protein activities, e.g., Joubert Syndrome and RelatedDisorders (JSRD) and other ciliopaties, including Meckel Syndrome (MKS),particularly in the Ashkenazi Jewish population. For this purpose, amutant TMEM216 protein or fragment thereof containing a particularvariation in accordance with the invention can be used in any of avariety of drug screening techniques. Drug screening can be performed asdescribed herein or using well known techniques, such as those describedin U.S. Pat. Nos. 5,800,998 and 5,891,628, both of which areincorporated herein by reference. The candidate therapeutic (the test)compounds may include, but are not limited to: proteins, small peptidesor derivatives or mimetics thereof; non-peptide small molecules;carbohydrates; nucleic acids; lipids or fats; and analogs thereof. Inanother embodiments, the compounds are small organic molecules having amolecular weight of no greater than 10,000 dalton, more or less than5,000 dalton.

In one embodiment of the invention, the screening method of theinvention is based on binding affinities to screen for compounds capableof interacting with or binding to a TMEM216 protein variant. Compoundsto be screened may be peptides or derivatives or mimetics thereof, ornon-peptide small molecules. In alternative embodiments, commerciallyavailable combinatorial libraries of compounds or phage displaylibraries displaying random peptides are used. In alternativeembodiments any screening techniques known in the art is used topractice the invention.

In alternative embodiments, the TMEM216 proteins of the invention (theTMEM216 variants are the putative drug target) can be prepared by anysuitable methods, e.g., by recombinant expression, by synthetic methods,or by purification. In alternative embodiments, a polypeptide orfragment can be free in solution or can be immobilized on a solidsupport, e.g., in a protein microchip, or on a cell surface. Inalternative embodiments, any techniques for immobilizing proteins on asolid support is used, e.g., example, PCT Publication WO 84/03564, whichdiscloses synthesizing a large numbers of small peptide test compoundson a solid substrate, such as plastic pins or other surfaces.Alternatively, purified mutant TMEM216 protein, or fragments thereof,can be coated directly onto plates such as multi-well plates.Non-neutralizing antibodies, i.e., antibodies capable binding to theTMEM216 protein, or fragments thereof, that do not substantially affectits biological activities may also be used for immobilizing the TMEM216protein, or fragments thereof, on a solid support.

In alternative embodiments, to affect the screening, test compounds canbe contacted with the immobilized TMEM216 protein of the invention, orfragments thereof, to allow binding to occur and complexes to form understandard binding conditions. In alternative embodiments, either the drugtarget or test compounds are labeled with a detectable marker using wellknown labeling techniques. To identify binding compounds, one maymeasure the steady state or end-point formation of the drug target-testcompound complexes, or kinetics for the formation thereof.

In alternative embodiments, a known ligand capable of binding to thedrug target can be used in competitive binding assays. Complexes betweenthe known ligand and the drug target can be formed and then contactedwith test compounds. The ability of a test compound to interfere withthe interaction between the drug target and the known ligand is measuredusing known techniques. One exemplary ligand is an antibody capable ofspecifically binding the drug target. In alternative embodiments, anantibody is used for identifying peptides that share one or moreantigenic determinants of a TMEM216 protein of the invention, orfragments thereof, or for identifying antigenic determinants specific toa TMEM216 protein (variants) of the invention.

In another embodiment, a yeast two-hybrid system may be employed toscreen for proteins or small peptides capable of interacting with aTMEM216 protein variant. For example, a battery of fusion proteins eachcontaining a random small peptide fused to e.g., Gal 4 activationdomain, can be co-expressed in yeast cells with a fusion protein havingthe Gal 4 binding domain fused to a TMEM216 protein variant. In thismanner, small peptides capable of interacting with the TMEM216 proteinvariant can be identified. Alternatively, compounds can also be testedin a yeast two-hybrid system to determine their ability to inhibit theinteraction between the TMEM216 protein variant and a known protein,which is known to interact with the TMEM216 protein or polypeptide orfragment thereof. One example of such proteins is an antibodyspecifically against the TMEM216 protein variant.

In alternative embodiments, yeast two-hybrid systems known in the artare used e.g., as disclosed in, e.g., Bartel et al., in: CellularInteractions in Development: A Practical Approach, Oxford UniversityPress, pp. 153-179 (1993); Fields and Song, Nature, 340:245-246 (1989);Chevray and Nathans, Proc. Natl. Acad. Sci. USA, 89:5789-5793 (1992);Lee et al., Science, 268:836-844 (1995); and U.S. Pat. Nos. 6,057,101,6,051,381, and 5,525,490.

In alternative embodiments, the compounds thus identified can be furthertested for activities, e.g., in stimulating the mutant TMEM216biological activities, e.g., in ciliogenesis and in interacting with itsknown interacting partner proteins. In alternative embodiments, once aneffective compound is identified, structural analogs or mimetics thereofcan be produced based on rational drug design with the aim of improvingdrug efficacy and stability, and reducing side effects. Methods known inthe art for rational drug design can be used in the invention. See,e.g., Hodgson et al., Bio/Technology, 9:19-21 (1991); U.S. Pat. Nos.5,800,998 and 5,891,628, all of which are incorporated herein byreference. An example of rational drug design is the development of HIVprotease inhibitors. See Erickson et al., Science, 249:527-533 (1990).In alternative embodiments, rational drug design is based on one or morecompounds selectively binding to a mutant TMEM216 protein or a fragmentthereof.

In one embodiment, the three-dimensional structure of, e.g., a TMEM216protein variant, is determined by biophysical techniques such as X-raycrystallography, computer modeling, or both. In alternative embodiments,the structure of the complex between an effective compound and themutant TMEM216 protein is determined, and the structural relationshipbetween the compound and the protein is elucidated. In this manner, themoieties and the three-dimensional structure of a selected compound(from a screening method of the invention), e.g., a lead compound,critical to its binding to a TMEM216 protein of this invention arerevealed. In alternative embodiments, analog compounds having similarmoieties and structures are designed. In alternative embodiments, thethree-dimensional structure of wild-type TMEM216 protein is decipheredand compared to that of a TMEM216 protein of the invention. Inalternative embodiments, this will aid in designing compoundsselectively interacting with a mutant TMEM216 protein.

In alternative embodiments, a selected peptide compound capable ofbinding the TMEM216 protein variant is analyzed by alanine scanningmutagenesis, e.g., as by Wells, et al., Methods Enzymol., 202:301-306(1991). In this technique, an amino acid residue of the peptide isreplaced by Alanine, and its effect on the peptide's binding affinity tothe mutant TMEM216 protein is tested. Amino acid residues of theselected peptide are analyzed in this manner to determine the domains orresidues of the peptide important to its binding to mutant TMEM216protein. These residues or domains constituting the active region of thecompound are known as its “pharmacophore”. This information can be veryhelpful in rationally designing improved compounds. Once thepharmacophore has been elucidated, a structural model can be establishedby a modeling process which may include analyzing the physicalproperties of the pharmacophore such as stereochemistry, charge,bonding, and size using data from a range of sources, e.g., NMRanalysis, x-ray diffraction data, alanine scanning, and spectroscopictechniques and the like. Various techniques including computationalanalysis, similarity mapping and the like can all be used in thismodeling process. See e.g., Perry et al., in OSAR: QuantitativeStructure-Activity Relationships in Drug Design, pp. 189-193, Alan R.Liss, Inc., 1989; Rotivinen et al., Acta Pharmaceutical Fennica,97:159-166 (1988); Lewis et al., Proc. R. Soc. Lond., 236:125-140(1989); McKinaly et al., Annu. Rev. Pharmacol. Toxiciol., 29:111-122(1989). Commercial molecular modeling systems available from PolygenCorporation, Waltham, Mass., include the CHARMm program, which performsthe energy minimization and molecular dynamics functions, and QUANTAprogram which performs the construction, graphic modeling and analysisof molecular structure. Such programs allow interactive construction,visualization and modification of molecules. Other computer modelingprograms are also available from BioDesign, Inc. (Pasadena. Calif.),Hypercube, Inc. (Cambridge, Ontario), and Allelix, Inc. (Mississauga,Ontario, Canada).

In alternative embodiments, a template is formed based on theestablished model. Various compounds can then be designed by linkingvarious chemical groups or moieties to the template. Various moieties ofthe template can also be replaced. In addition, in the case of a peptidelead compound, the peptide or mimetics thereof can be cyclized, e.g., bylinking the N-terminus and C-terminus together, to increase itsstability. These rationally designed compounds are further tested. Inthis manner, pharmacologically acceptable and stable compounds withimproved efficacy and reduced side effect can be developed.

Cell and Animal Models

In alternative embodiments, the invention provides transduced ortransfected cells, or cell lines, or non-human transgenic animals,comprising (e.g., carrying, or having contained therein) a nucleic acidor a polypeptide of this invention, e.g., a TMEM216 nucleic acid orTMEM216 protein variant of the invention. The cells, cell lines and/ornon-human transgenic animals can be used as screening or model systemsfor studying ciliopathies and testing various therapeutic approaches intreating ciliopathies, e.g., JSRD and MKS.

In alternative embodiments, to establish the cell line, cells expressinga polypeptide of this invention, e.g., a mutant TMEM216 protein, issynthesized or cloned, or isolated from an individual carrying a TMEM216genetic variant. The primary cells can be transformed or immortalizedusing techniques known in the art. Alternatively, normal cellsexpressing a wild-type TMEM216 protein or other type of genetic variantscan be manipulated to replace the entire endogenous TMEM216 gene with aTMEM216 nucleic acid (variant) of the invention, or simply to introducemutations into the endogenous TMEM216 gene. The genetically engineeredcells can further be immortalized.

In alternative embodiments, non-human transgenic animals are used forscreening or testing. A transgenic animal can be made by replacing itsendogenous TMEM216 gene ortholog with a heterologous nucleic acidsequence of the invention (e.g., a human TMEM216 nucleic acid variant).Alternatively, deletions, insertions or substitutions can be introducedinto the endogenous animal TMEM216 gene ortholog to simulate the TMEM216of the invention. In alternative embodiments, any technique for making anon-human transgenic animal is used, e.g., as described in, e.g.,Capecchi, et al., Science, 244:1288 (1989); Hasty et al., Nature,350:243 (1991); Shinkai et al., Cell, 68:855 (1992); Mombaerts et al.,Cell, 68:869 (1992); Philpott et al., Science, 256:1448 (1992);Snouwaert et al., Science, 257:1083 (1992); Donehower et al., Nature,356:215 (1992); Hogan et al., Manipulating the Mouse Embryo; ALaboratory Manual, 2nd edition, Cold Spring Harbor Laboratory Press,1994; and U.S. Pat. Nos. 5,800,998, 5,891,628, and 4,873,191.

In alternative embodiments, these cells, cell lines and non-humantransgenic animals are valuable tools for studying the mutant TMEM216genes, and e.g., for testing in vivo the compounds identified in the invitro or cell-based screening methods of this invention. Studying drugcandidates in a suitable animal model before advancing them into humanclinical trials is particularly important because not only can efficacyof the drug candidates can be confirmed in the model animal, but thetoxicology profiles, side effects, and dosage ranges can also bedetermined. Such information is then used to guide human clinicaltrials.

Although the foregoing invention has been described in some detail byway of illustration and example for purposes of clarity ofunderstanding, it will be obvious that certain changes and modificationsmay be practiced within the scope of the appended claims.

All publications mentioned in the specification are indicative of thelevel of those skilled in the art to which this invention pertains. Allpublications and patent applications are herein incorporated byreference to the same extent as if each individual publication or patentapplication was specifically and individually indicated to beincorporated by reference.

The invention will be further described with reference to the examplesdescribed herein; however, it is to be understood that the invention isnot limited to such examples.

EXAMPLES

Aspects of the present teachings may be further understood in light ofthe following examples, which should not be construed as limiting thescope of the present teachings in any way.

Example 1—JSRD and MKS Studies

Research Subjects.

After obtaining informed consent from parents, we used standard methodsto isolate genomic DNA from peripheral blood of the affected childrenand family members or from frozen fetal tissue or amniocytes.Experiments were done in accordance with local ethics committeerecommendations. Pregnancies were terminated after genetic counseling,in accordance with local bioethics laws and guidelines. Chromosomeanalysis was performed for at least one fetus of each family. Informedconsent for the use of DNA and tissue was obtained from allparticipating families and the studies were approved by the EthicsBoards of Leeds (East), Casa Sollievo della SofferenzaHospital/CSS-Mendel Institute. Hôpital Necker-Enfants Malades, and UCSD.

Genetic Mapping.

To refine the MKS2/JBTS2 locus, the 10K Affymetrix SNP array was used toperform a total genome-wide search for linkage in 9 consanguineousfamilies with MKS. Data was evaluated by performing multipoint linkageanalysis using MERLIN software assuming a fully penetrant recessivemodel with a disease allele of frequency 0.001 and allowing forheterogeneity between families. Areas of homozygosity on chromosome 11were confirmed by performing high-resolution haplotype analysis withinthe identified regions. Published microsatellite markers were used.

Mutation Screening.

Mutational screening of TMEM216 was performed by direct sequencing ofthe 6 coding exons and the adjacent intronic junctions in JSRD/MKSfamilies showing potential linkage to the locus and all MKS cases. PCRproducts were treated with EXO-SAP IT™ (AP Biotech), and both strandswere sequenced using a BIGDYE™ (BigDye) terminator cycle sequencing kitwith an ABI3130™ automated sequencer (Applied Biosystems). To test forTMEM216 mutations in the cohort of 460 JSRD patients we applied the highresolution melting (HRM) technique 31 using a LIGHTCYCLER (LightCycler)480™ (Roche Applied Science), with the same primers and optimized PCRconditions, see e.g., Supplemental Table 1, describing SEQ ID NO: 17;SEQ ID NO: 18; SEQ ID NO: 19; SEQ ID NO:20; SEQ ID NO:21; SEQ ID NO:22;SEQ ID NO:23; SEQ ID NO:24; SEQ ID NO:25; and SEQ ID NO:26, from top tobottom in Table 1:

Supplemental Table 1 Primer Sequence Anneal TMEM216ex1FGACCGTTATCGCTTAGGTCT 56 TMEM216ex1R TAGGTCAAGCTCTGGGACA TMEM216ex3FTAGACACCACCCATACGAG 56 TMEM216ex3R TTGGTAGGAATTGGCTCTG TMEM216ex4FTGGAAAGCTGAGAGTGATGT 56 TMEM216ex4R TACCAGCTTGTCTCATAAGGA TMEM216ex5FCATTCCATCACATCCCCAC 56 TMEM216ex5R ATGAGAAATGGTCCCTCAGC TMEM216ex6FGCTGCTCTCATTCACTGGTC 56 TMEM216ex6R ACAGCCTTTCTCAGGACAAC

Parental samples were tested to overcome the limit of HRM in identifyinghomozygous changes. In case parental samples were not available, theproband's DNA was mixed with equal amount of DNA from a wild-typeindividual (1:1). Each sample showing abnormal melting profile underwentdirect sequencing. Segregation of the identified mutations wasinvestigated in all available family members. Constructs encodingwildtype or mutant TMEM216 were transfected into 293T cells in a ratioof 20:1 TMEM216:TK-βgal vector. Cells were lysed after 48 h and half ofeach sample was subjected to Western analysis by blotting with EGFPantibody (Covance MMS-118R 1:500) and the remainder subjected to β-galassay to standardize transfection efficiency 32. Similar loading of eachwell was confirmed by blotting with α-tubulin (Sigma T9026 1:2000).

Founder Haplotype Analysis.

The region surrounding TMEM216 was saturated with 14 single nucleotidepolymorphisms and 3 microsatellite markers in ten patients homozygousfor the same p.R73L mutation. Estimation of the mutation age wascalculated as reported 33.

Bioinformatics.

Genetic location is in accordance with the 2006 Human Genome Browser (UCSanta Cruz, The Regents of the University of California). The fulllength TMEM216 open reading frame is encoded in EST BI910875. Theciliary proteome was searched using web-based tools 13,14. RefSeq wasaccessed using the NCBI Internet, NCBI Bethesda, Md., National Libraryof Medicine (US), National Center for Biotechnology Information. Pfam isweb-based and is supported e.g., by the Howard Hughes Medical Institute,Chevy Chase, Md.

Cloning.

Full-length TMEM216 was cloned into the pcDNA3.0 vector, and thenshuttled into the mCherry- and EGFP-containing vectors. Mutations wereintroduced into TMEM216-pEGFP-N3 by QUICKCHANGE™ (QuickChange)mutagenesis (Stratagene, San Diego Calif.). TMEM216 open reading framewas also cloned into pCS2+ vector in order to make RNA for injectioninto zebrafish embryos.

Cells and Antibodies.

Mouse inner medullary collecting duct (IMCD3), human hTERT-immortalizedretinal pigmentary epithelial (hRPE), and human embryonic kidney(HEK293) cells were grown in Dulbecco's minimum essential medium(DMEM)/Ham's F12 supplemented with 10% fetal calf serum at 37° C./5%C02. Fibroblasts were immortalized with the hTERT system, and maintainedin Fibroblast Growth Medium (Genlantis Inc., San Diego, Calif.)supplemented with 10% fetal calf serum and 0.2 mg/ml geneticin. Normal,undiseased control fibroblasts were gestationally-age matched tofibroblasts from MKS patients. Patient 186, a compound heterozygote forthe MKS3′TMEM67 mutations [p.R217X]+[p.M261T], has been describedpreviously 23. The following primary antibodies were used: mouseanti-GFP and rabbit A.V. peptide (“Living Colors”, Clontech):mouse-anti-γ-tubulin, mouse anti-acetylated-tubulin (Sigma-Aldrich Co.Ltd.); mouse-anti-glutamylated tubulin (GT335) 34,rabbit-anti-γ-tubulin, rabbit-anti-Meckelin, mouse anti-β actin (AbcamLtd.); mouse anti-filamin A (AbNova Inc.); mouse anti-Dvl1 (Santa CruzBiotechnology Inc.); mouse anti-RhoA (Cytoskeleton Inc.); and anti-EFe4(a gift from P. Robinson, Department of Ophthalmology & Neurosciences,University of Leeds, UK). Rabbit-anti-Meckelin C-terminus, raisedagainst amino acids 982-995, has been described previously 18.Rabbit-anti-Meckelin N-terminus, raised against amino acids 100-113, hasalso been described 23. Secondary antibodies were Alexa-Fluor488-Alexa-Fluor 594- and Alexa-Fluor 568-conjugated goat anti-mouse IgGand goat anti-rabbit IgG (Molecular Probes), and HRP-conjugated goatanti-mouse and goat anti-rabbit (Dako). Alexa-Fluor 488 and 633phalloidin conjugate (Molecular Probes) was used to visualize F-actin.

Biochemical Assays.

Rabbit-anti-TMEM216 antiserum was raised against the peptide sequenceNLCQRKMPLS (SEQ ID NO:27) or NLCQRKMPLSC (SEQ ID NO:28), comprisingamino acids 81-90, by GenScript Inc. (Piscatawav, N.J., USA). Antiserumwas precipitated with 50% [w/v] ammonium sulphate pH7.0 andaffinity-purified essentially as described previously 35.Co-immunoprecipitation was performed essentially as described previously35. Whole cell extracts (WCE) were prepared from confluent untransfectedHEK293 cells, or IMCD3 cells that had been transiently transfected with1.0 ug plasmid constructs in 90 mm tissue culture dishes, or scaled downas appropriate. WCE supernatants were processed for immunoprecipitationexperiments by using 5 μg affinity-purified mouse anti-GFP (“LivingColors”, Clontech Inc.), or 5 μg MAbs, or 5-10 μg purified IgG fractionsfrom rabbit polyclonal antisera, coupled to protein G- and/or proteinA-Sepharose beads (GE Healthcare UK Ltd.) Immunoprecipitations wereperformed in reduced salt incubation buffer (20 mM Tris, pH7.5, 25 mMNaCl, 2 mM EDTA, 0.5 mM EGTA, 0.02% [w/v] NaN3, 10% [v/v] glycerol, 10%[v/v] ethanol, 0.1% [v/v] protease inhibitor cocktail). For assessingDvl1 phosphorylation status, extraction and wash buffers weresupplemented with phosphatase inhibitor cocktail (Sigma).

In Situ Hybridization in Human Embryos.

Human embryos were collected from terminated pregnancies using themefiprestone protocol in agreement with French bioethics laws (94-654and 04-800). Embryos were fixed in 11% formaldehyde, 60% ethanol and 10%acetic acid, embedded in paraffin and sectioned at 5 μm. Primers wereselected for RT-PCR amplification on RNA extracted from a whole C12 (4w) embryo

F1: (SEQ ID NO: 29) GGTGAGATTCCGGAGGTAAACG, R4: (SEQ ID NO: 30)CCAAGGTGAGCACCTCAAGTused as template for generating the riboprobes. T7F/R and F/T7R primercombinations allowed the amplification of sense and antisense templatesrespectively, as described 36. Sections were hybridized with aDigoxygenin labeled probe at 70° C. overnight, and digoxygenin wasdetected with an anti-DIG-Fab′ antibody (Roche) at 1:1000.

Immunofluorescence and Confocal Microscopy.

IMCD3 or human age-matched hTERT-immortalized fetal fibroblasts wereseeded at 20×103 cells/well on glass coverslips in six-well plates andfixed in ice-cold methanol (5 minutes at 4° C.) or 2% paraformaldehyde(20 minutes at room-temp). For analysis of siRNA-treated cells, cellswere extracted in 0.75% Triton X-100 in 100 mM PIPES pH 6.9, 2 mM EGTA,1 mM MgSO4, 0.1 mM EDTA for 30 seconds and fixed in methanol at −20° C.for at least 10 minutes. Paraformaldehyde fixed cells were permeabilizedwith 0.1% Triton X-100. For immunofluorescence, cells were washed withPBS and blocked in 1% milk protein/PBS. Primary and secondary antibodiestogether with DAPI (2 mg/ml), were added in 1% milk protein/PBS each foran hour, with further PBS washes between each stage. Primary antibodieswere used at the following dilutions: mouse anti-acetylated-tubulin(1:800); mouse-anti-glutamylated tubulin (GT335) (1:1000);rabbit-anti-γ-tubulin (1:500); rabbit-anti-Meckelin (1:50-1:250); rabbitanti-TMEM216 (1:200); mouse anti-filamin A (1:500); mouse-anti-RhoA(1:1000). Secondary antibodies and phalloidin conjugate were diluted1:500, and DAPI was diluted 1:1000. Confocal images were obtained usinga Nikon Eclipse TE2000-E system, controlled by EZC 1 3.50 (Nikon)software. Images were processed in Metamorph, and figures were assembledusing Adobe Photoshop CS3.

Transfection and siRNA.

For transfection with plasmids, cells at 90% confluency were transfectedusing Lipofectamine 2000 (Invitrogen Inc.) according to themanufacturer's instructions. Cells were incubated for 24 to 72 hrs priorto lysis or immunostaining. For RNAi knockdown in IMCD3 cells, siRNAduplexes were designed against different regions of the mouse Tmem216(“Stealth Select”. Invitrogen Inc.) Sequences were as follows:

Tmem216 siRNA1: (SEQ ID NO: 31) 5′-GCU GCU GCU CUA UCU UGG CAU UGA A,Tmem216 siRNA2: (SEQ ID NO: 32) 5′-CCC UUG GCA UUA GUG UGG CCU UGA C,Tmem216 siRNA3: (SEQ ID NO: 33) 5′-CCC AUC CGC UAU GAU GGC UUC CUA U.

Semi-quantitative RT-PCR analysis demonstrated the effectiveness of theTmem216 siRNA1 (FIG. 14). Mks3 siRNA reagents have been describedpreviously (23). The medium or low GC nontargeting negative controls(Invitrogen) were used as scrambled siRNA controls. Irrelevant siRNAduplexes against Hhari were used as a second negative control (a giftfrom P. Robinson, Department of Ophthalmology & Neurosciences,University of Leeds, UK). Individual duplexes (20 nM) or siRNA pools(total 60 nM) were transfected into IMCD3 cells at 60-80% confluencyusing LIPOFECTAMINE 2000® RNAiMAX™ (Invitrogen Inc.) according to themanufacturer's instructions. The efficiency of siRNA transfections, asdetermined with BLOCK-iT® Fluorescent Oligo (Invitrogen Inc.), wasgreater than 60%. Further assays were carried out at 72 hours aftertransfection.

RhoA Activation Assay.

The activated GTP-bound isoform of RhoA was specifically assayed inpull-down assays using a GST fusion protein of the Rho effector rhotekin(Cytoskeleton Inc., CO, USA), using conditions recommended by themanufacturers. Cell lysates were processed as rapidly as possible at 4°C., and snap-frozen in liquid nitrogen. Total RhoA and pull-down proteinwas immunodetected on western blots using a proprietary anti-RhoAmonoclonal antibody (Cytoskeleton Inc.) Rho activity was inhibited bytreating cells with cell permeable exoenzyme-C3-transferase(Cytoskeleton Inc.) at 2 ug/ml for 5 hr under standard cell cultureconditions. Results shown are representative of three separateexperiments.

Identification of Ciliary Defect Phenotypes in Zebrafish.

To knockdown tmem216 in zebrafish, a translational blocking morpholinoantisense oligonucleotides (MOs) (5′-GGTTGTCTTCCGTGGGCAGCCATGT-3′) (SEQID NO:34) (Gene Tools, Philomath, Oreg.) or control was microinjected (4ng/nl) into one-two cell stage embryos, obtained from natural spawningof wild-type (AB) zebrafish lines. The mRNA encoding full-length humanTMEM216 was co-injected where indicated. Endogenous mks3 was suppressedwith a splice-blocking MO described previously (3 ng/nl) 29. Forassessment of gastrulation phenotypes, mid-somitic embryos were scoredblind at 8 somites (live; 80-100 embryos/injection), or 10-11 somites(morphometric analyses). Embryos were fixed overnight in 4% PFA,hybridized in situ with DIG-labeled krox20, pax2, and myoD riboprobesaccording to standard protocols, and flat-mounted for imaging andanalysis. At 3 days postfertilization, morphological phenotype ofmorphants were quantified under bright-field microscopy based uponciliary defects (hydrocephalus, small brain, heart edema, and curvedtail) or embryonic lethal phenotypes.

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APPENDIX A SEQ ID NO: 1-TMEM216 amino acid sequence (148 aa)MLPRGLKMAP RGKRLSSTPL EILFFLNGWY NATYFLLELF IFLYKGVLLP YPTANLVLDV  60VMLLLYLGIE VIRLFFGTKG NLCQRKMPLS ISVALTFPSA MMASYYLLLQ TYVLRLEAIM 120NGILLFFCGS ELLLEVLTLA AFSSMDTI 148SEQ ID NO: 2-TMEM216 EST (GenBank Accession No. BI910875.1)ctgcagacga cggcgtcgtg ggtggtcacc gttatccctt aggtctggag aggggacatc  60cgagcgaggg ccacttgcgg ccaggcccga gctcgtccag ctccgggtga ccacagagtg 120ccgcgggcgg gcagaggggc cggaaaccca ggccgcttcg tccctgtttc cggcagcgcc 180gcgctgctcc gggagccgct gtggcagcgt atgctgccac ggggactgaa gatggcgccg 240cgaggtaaac ggttgtcctc caccccgctg gaaatcctgt tctttctgaa cgggtggtat 300aatgctacct atttcctgct ggaacttttc atatttctgt ataaaggtgt cctgctacca 360tatccaacag ctaacctagt actggatgtg gtgatgctcc tcctttatct tggaattgaa 420gtaattcgcc tgttttttgg tacaaaggga aacctctgcc agcgaaagat gccactcagt 480attagcgtgg ccttgacctt cccatctgcc atgatggcct cctattacct gctgctgcag 540acctacgtac tccgcctgga agccatcatg aatggcatct tgctcttctt ctgtggctca 600gagcttttac ttgaggtgct caccttggct gctttctcca gtatggacac gatttgaagt 660acagaatttc agccagcagc ccatcaggct gacaccacac atattgcttc tggtacttta 720gccacaccag tgagaattgg tggggcaagt tgtcctgaga aaggctgtgt ggcttttctt 780cagcacagac ctttgggcaa ggcaactcag cataaggccg tgggtaccat cttctaaaac 840caggaccatc caggccaaga ga 862SEQ ID NO: 3-Nucleotide sequence encoding 148 aa TMEM216 (SEQ ID NO: 1)atgctgccac ggggactgaa gatggcgccg cgaggtaaac ggttgtgctc caccccgctg  60gaaatcctgt tctttctgaa cgggtggtat aatgctacct atttcctgct ggaacttttc 120atatttctgt ataaaggtgt cctgctacca tatccaacag ctaacctagt actggatgtg 180gtgatgctcc tcctttatct tggaattgaa gtaattcgcc tgttttttgg tacaaaggga 240aacctctgcc agcgaaagat gccactcagt attagcgtgg ccttgacctt cccatctgcc 300atgatggcct cctattacct gctgctgcag acctacgtac tccgcctgga agccatcatg 360aatggcatct tgctcttctt ctgtggctca gagcttttac ttgaggtgct caccttggct 420gctttctcca gtatggacac gatttga 447 SEQ ID NO: 4-BC011010 mRNAgtgggtggtc accgttatcc cttaggtctg gagaggggac atccgagcga gggccacttg   60cggccaggcc cgagctcgtc cagctccggg tgaccacaga gtgccgcggg cgggcagagg  120ggccggaaac ccaggccgct tcgtccctgt ttccggcagc gccgcgctgc tccgggagcc  180gctgtggcag cgtatgctgc cacggggact gaagatggcg ccgcgaggtg agattccgga  240ggtaaacggt tgtcctccac cccgctggaa atcctgttct ttctgaacgg gtggtataat  300gctacctatt tcctgctgga acttttcata tttctgtata aaggtgtcct gctaccatat  360ccaacagcta acctagtact ggatgtggtg atgctcctcc tttatcttgg aattgaagta  420attcgcctgt tttttggtac aaagggaaac ctctgccagc gaaagatgcc actcagtatt  480agcgtggcct tgaccttccc atctgccatg atggcctcct attacctgct gctgcaaacc  540tacgtactcc gcctggaagc catcatgaat ggcatcttgc tcttcttctg tggctcagag  600cttttacttg aggtgctcac cttggctgct ttctccagta tggacacgat ttgaagtaca  660gaatttcagc cagcagicca tcaggctgac accacacata tttgcttctg gtactttagc  720cacaccagtg agaattggtg gggcaagttg tcctgagaaa ggctgtgtgg cttttcttca  780gcacagacat ttgggcaagc aactcagcat aaggccagtg ggtaccatct tctaaaccag  840gaccatcagc ccaagagact cttctacact ccagtatagg gaggggcaag gttattccca  900tcctgcccct tctcagaacc agtcccctgc tgacctcaag ttctcctcct tgatcaccgt  960ggccagagca tctcgtgtgg accatctagg ctccttgggc ttcaagcagg acctgagcca 1020catgctccct gtacgagctg tgctatacct gtcccacatg agcacggaga gcctcatgtt 1080ggtgggtttc cagagtgatg tgaaagcctc tcaccccaat cctcggagac tgagttccac 1140aactttttta gtagctcata gtgttatttt tctactctct tcatgaaa 1188SEQ ID NO: 5-BC011010 nucleotide seguence encoding 30 aa (SEQ ID NO: 6)atgctgccac ggggactgaa gatggcgccg cgaggtgaga ttccggagg aaacggttgt 60cctccacccc gctggaaatc ctgttotttc tga 93SEQ ID NO: 6-BC0110101, amino acid seguence (30 a.a.)MLPRGLKMAP RGEIPEVNGC PPPRWKSCSF 30 SEQ ID NO: 7-cDNA clones (44)gtgggtggtc accgttatcc cttaggtctg gagaggggac atccgagcga gggccacttg   60cggccaggcc cgagctcgtc cagctccggg tgaccacaga gtgccgcggg cgggcagagg  120ggccggaaac ccaggccgct tcgtccctgt ttccggcagc gccgcgctgc tccgggagcc  180gctgtggcag cgtatgctgc cacggggact gaagatggcg ccgcgagcgt tagggacgtc  240gcgcctccct ggtccaaagc cggcttccgc ggtcccgccc accctgggtg cctgaaggtc  300tcaaggtgca cagctcaaat aaacgcacct ccttggctgg gccacttcta ggctggctca  360ggtaaacggt tgtcctccac cccgctggaa atcctgttct ttctgaacgg gtggtataat  420gctacctatt tcctgctgga acttttcata tttctgtata aaggtgtcct gctaccatat  480ccaacagcta acctagtact ggatgtggtg atgctcctcc tttatcttgg aattgaagta  540attcgcctgt tttttggtac aaagggaaac ctctgccagc gaaagatgcc actcagtatt  600agcgtggcct tgaccttccc atctgccatg atggcctcct attacctgct gctgcagacc  660tacgtactcc gcctggaagc catcatgaat ggcatcttgc tcttcttctg tggctcagag  720cttttacttg aggtgctcac cttggctgct ttctccagta tggacacgat ttgaagtaca  780gaatttcagc cagcagccca tcaggctgac accacacata ttgcttctgg tactttagcc  840acaccagtga gaattggtgg ggcaagttgt cctgagaaag gctgtgtggc ttttcttcag  900cacagacatt tgggcaagca actcagcata aggccagtgg gtaccatctt ctaaaccagg  960accatcagcc caagagactc ttctacactc cagtataggg aggggcaagg ttattcccat 1020cctgcccctt ctcagaacca gtcccctgct gacctcaagt tctcctcctt gatcaccgtg 1080gccagagcat ctcgtgtgga ccatctaggc tccttgggct tcaagcagga cctgagccac 1140atgctccctg tacgagctgt gctatacctg tcccacatga gcacggagag cctcatgttg 1200gtgggtttcc agagtgatgt gaaagcctct caccccaatc ctcggagact gagttccaca 1260acttttttag tagctcatag tgttattttt ctactctctt catgaaa 1307SEQ ID NO: 8-cDNA clone 44 nucleotide seguencing encoding 33 aa (SEQ ID NO: 9)atgctgccac ggggactgaa gatggcgccg cgagcgttag ggacgtcgcg cctccctggt  60ccaaagccgg cttccgcggt cccgcccacc ctgggtgcct ga 102SEQ ID NO: 9-Amino acid seguence of cDNA clone 44MLPRGIKMAP RALGTSRLPG PKPASAVPPT LGA 33 SEQ ID NO: 10-cDNA clones (28)gtggctggtc accgttatcc cttcctgggt gcctgaaggt ctcaaggtgc acagctcaaa   60taaacgcaga tccttggctg ggccacttct aggctggctc aggtaaacgg ttgtcctcca  120ccccgctgga aatcctgttc tttctgaacg ggtggtataa tgctacctat ttcctgctgg  180aacttttcat atttctgtat aaaggtgtcc tgctaccata tccaacagct aacctagtac  240tggatgtggt gatgctcctc ctttatcttg gaattgaagt aattcgcctg ttttttggaa  300aagcagacca tttggagatg actccatggg ctgtgtctga caggtacaaa gggaaacctc  360tgccagcgaa agatgccact cagtattagc gtggccttga ccttcccatc tgccatgatg  420gcctcctatt acctgctgct gcagacctac gtactccgcc tggaagccat catgaatggc  480atcttgctct tcttctgtgg ctcagagctt ttacttgagg tgctcacctt ggctgctttc  540tccagtatgg acacgatttg aagtacagaa tttcagccag cagcccatca ggctgacacc  600acacatattg cttctggtac tttagccaca ccagtgagaa ttggtggggc aagttgtcct  660gagaaaggct gtgtggcttt tcttcagcac agacatttgg gcaagcaact cagcataagg  720ccagtgggta ccatcttcta aaccaggacc atcagcccaa gagactcttc tacactccag  780tatagggagg ggcaaggtta ttcccatcct gccccttctc agaaccagtc ccctgctgac  840ctcaagttct cctccttgat caccgtggcc agagcatctc gtgtggacca tctaggctcc  900ttgggcttca agcaggacct gagccacatg ctccctgtac gagctgtgct atacctgtcc  960cacatgagca cggagagcct catgttggtg ggtttccaga gtgatgtgaa agcctctcac 1020cccaatcctc ggagactgag ttccacaact tttttagtag ctcatagtgt tatttttcta 1080ctctcttcat gaaa 1094SEQ ID NO: 11-cDNA clone 28 nucleotide seguence encoding 25 aa (SEQ ID NO: 12)atgctaccta tttcctgctg gaacttttca tatttctgta taaaggtgtc ctgctaccat 60atccaacage taacctag 78 SEQ ID NO: 12-cDNA clone 28 amino acid seguenceMLPISCWNES YECIKVSCYH IQQLT 25SEQ ID NO: 13 and SEQ ID NO: 14: PCR primers located in TMEM216 exon 4forward: GATGTGGTGATGCTCCTCCT (SEQ ID NO: 13) andreverse: CCAAGGTGAGCACCTCAAGT (SEQ ID NO: 14).TMEM216 WT seguence is SEQ ID NO: 15:GTACAAA GGGAAACCTC TGCCAGCGAA AGATGCCACT CAGTATTAGC GTGGCCTTGA CCTTCTMEM216 Mut seguence is SEQ ID NO: 16:GAAAA GCAGA CCATT TGGAG ATGAC TCCAT GGGCT GTGTC TGACA GCTAC AAAGG GAAAC CTSEQ ID NO: 17 CACCGTTATCCCTTAGGTCT SEQ ID NO: 18 TAGGTCAAGCTCTGGGACASEQ ID NO: 19 TAGACACCAACCCATACGAG SEQ ID NO: 20 TTGGTAGGAATTGGCTCTGSEQ ID NO: 21 TGGAAAGCTGAGACTGATGT SEQ ID NO: 22 TACCAGCTTGTCTCATAAGGASEQ ID NO: 23 CATTCCATCACATCTCCCAC SEQ ID N0: 24 ATGAGAAATGGTCCCTCAGCSEQ ID NO: 25 GCTGCTCTCATTCACTGGTC SEQ ID NO: 26 ACAGCCTTTCTCAGGACAAC

A number of embodiments of the invention have been described.Nevertheless, it will be understood that various modifications may bemade without departing from the spirit and scope of the invention.Accordingly, other embodiments are within the scope of the followingclaims.

What is claimed is:
 1. A method of detecting or identifying a variantTransmembrane Protein 216 (TMEM216) gene in an individual, comprising:(i) providing a sample from an individual, wherein the sample comprisesa nucleic acid; (ii) contacting the TMEM216 encoding nucleic acid in thesample with a probe capable of hybridizing to a TMEM216 encoding nucleicacid sequence variant, wherein the TMEM216 encoding nucleic acidsequence variant encodes an amino acid variation of SEQ ID NO:1 selectedfrom the group consisting of L133X, L114R, G77A, R85X, wherein the probeis labeled with a detectable marker, and wherein the selectable markeris selected from the group consisting of a radioisotope, fluorescentcompound, biotin, enzyme, enzyme co-factor, ligand, and antibody, and(iii) detecting hybridization of the probe with the TMEM216 encodingnucleic acid sequence variant, wherein detection of hybridizationdetects or identifies the presence of a variant TMEM216 gene in thesample from the individual.
 2. The method of claim 1, wherein the aminoacid variation comprises L133X.
 3. The method of claim 1, wherein theamino acid variation comprises s L114R.
 4. The method of claim 1,wherein the amino acid variation comprises G77A.
 5. The method of claim1, wherein the amino acid variation comprises R85X.
 6. The method ofclaim 1, wherein the method comprises isolating the TMEM216-encodingnucleic acid from the sample before detecting hybridization of the probewith the TMEM216-encoding nucleic acid sequence variant.
 7. The methodof claim 1, wherein the TMEM216-encoding nucleic acid comprises aTMEM216 RNA, a TMEM216 DNA, a TMEM216 cDNA or a TMEM216 genomic DNA. 8.The method of claim 1, wherein the method further comprises analyzing orsequencing the TMEM216-encoding nucleic acid by performing a techniquecomprising: a polymerase chain reaction (PCR) assay; a chain-terminatormethod; an emulsion PCR assay; an oligonucleotide ligation and detectionmethod; a high-throughput sequencing; a DNA nanoball sequencing; aMassive Parallel Signature Sequencing (MPSS); a dye-terminatorsequencing procedure; a reversible dye-terminator sequencing procedure;an ion semiconductor sequencing; a parallelized version ofpyrosequencing; or, any combination thereof.
 9. The method of claim 8,wherein the technique comprises a PCR assay.
 10. The method of claim 8,wherein the technique comprises high-throughput sequencing.
 11. Themethod of claim 1, wherein the enzyme is an alkaline phosphatase.